Patent Publication Number: US-9843667-B2

Title: Electronic device and call service providing method thereof

Description:
CLAIM OF PRIORITY 
     This application claims the benefit under 35 U.S.C. §119(a) of a Korean patent application filed on Nov. 25, 2015, in the Korean Intellectual Property Office and assigned Serial No. 10-2015-0165384, the entire disclosure of which is hereby incorporated by reference. 
     BACKGROUND 
     1. Field of the Disclosure 
     The present disclosure relates to a method and apparatus for controlling a plurality of calls. 
     2. Description of Related Art 
     Electronic devices have been developed to provide various functions. Examples of such functions include allowing the user of the electronic device to take still images, videos, etc., multimedia playback, e.g., playing music files, video files, etc., games, navigation services, etc. 
     Electronic devices also provide communication services such as voice communications and SMS/MMS text messages, etc. 
     Typically, when the user is in a voice communication session, i.e. a voice call with another user, the user may receive a new call from a third user. In those instances, the user may need to select one of the existing call and the new call, and hold or reject the other call. 
     SUMMARY 
     The present disclosure has been made to address the above problems and disadvantages, and to provide at least the advantages described below. Various embodiments of the present disclosure provide a call service providing method which is capable of performing calls with a number of parties simultaneously, including an existing call of the user and a new call that the user receives. Various embodiments of the present disclosure also provide an electronic device adapted to the call service providing method thereof. 
     In accordance with an aspect of the present disclosure, an electronic device is provided. The electronic device includes: at least one communication circuit supporting at least one communication protocol; a display; a microphone; a speaker; an input device which is configured with or separated from the display; a control circuit electrically coupled to the communication circuit, the display, the microphone, the speaker, and the input device; and a memory electrically coupled to the control circuit. The memory stores instructions executable by the control circuit to: receive a first call from a first external electronic device via the at least one communication circuit; during the first call, receive a request for a second call from a second external electronic device via the at least one communication circuit; receive the second call based on input via the input device; convert a first voice data from the second external electronic device to a first text data and display the first text data on the display; and convert a second text data inputted via the input device to a second voice data and transmit the second voice data to the second external electronic device. 
     In accordance with another aspect of the present disclosure, an electronic device is provided. The electronic device includes: a communication module; and a control circuit. The control circuit is configured to: receive a request for a second call from a second party while the electronic device is connected with a first party in a first call; and control the communication module to connect the second call with the second party while maintaining the first call, according to an input from a user of the electronic device, wherein the first call is connected in a first communication mode and the second call is connected in a second communication mode. 
     In accordance with another aspect of the present disclosure, a call service providing method of an electronic device is provided. The method includes: receiving a first call from a first external electronic device via at least one communication circuit; during the first call, receiving a request for a second call from a second external electronic device via the at least one communication circuit; receiving the second call based on input via an input device; converting a first voice data from the second external electronic device to a first text data and displaying the first text data on the display; and converting a second text data inputted via the input device to a second voice data and transmitting the second voice data to the second external electronic device. 
     In accordance with another aspect of the present disclosure, a call service providing method of an electronic device is provided. The method includes: providing a user of the electronic device with a first call from a first party; receiving a request for a second call from a second party while providing the first call; and controlling a communication module to connect the second call with the second party while maintaining the first call, according to an input from a user of the electronic device, wherein the first call is connected in a first communication mode and the second call is connected in a second communication mode. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The above and other aspects, features and advantages of the invention will be more apparent from the following detailed description, taken in conjunction with the accompanying drawings, in which: 
         FIG. 1  is a block diagram showing a network environment including electronic devices according to one embodiment of the present disclosure; 
         FIG. 2  is a block diagram of an electronic device according to one embodiment of the present disclosure; 
         FIG. 3  is a block diagram of one or more program modules according to one embodiment of the present disclosure; 
         FIG. 4  is a block diagram showing a network environment including electronic devices according to one embodiment of the present disclosure; 
         FIG. 5  is a detailed block diagram of an electronic device according to one embodiment of the present disclosure; 
         FIG. 6  is a flowchart that describes a call service providing method of an electronic device according to one embodiment of the present disclosure; 
         FIG. 7  is a flow diagram that describes a method of simultaneously performing first and second calls according to one embodiment of the present disclosure; 
         FIG. 8  is a flowchart that describes a call service providing method of an electronic device according to one embodiment of the present disclosure; 
         FIG. 9  is a flowchart that describes a method of performing a third call according to one embodiment of the present disclosure; 
         FIG. 10  is a flowchart that describes a call service providing method of an electronic device according to one embodiment of the present disclosure; and 
         FIG. 11  is a flowchart that describes a call service providing method of an electronic device according to one embodiment of the present disclosure. 
     
    
    
     DETAILED DESCRIPTION 
     The following description with reference to the accompanying drawings is provided to assist in a comprehensive understanding of various embodiments of the present disclosure as defined by the claims and their equivalents. It includes various specific details to assist in that understanding but these are to be regarded as merely exemplary. Accordingly, those of ordinary skill in the art will recognize that various changes and modifications of the various embodiments described herein can be made without departing from the scope and spirit of the present disclosure. In addition, descriptions of well-known functions and constructions may be omitted for clarity and conciseness. 
     The terms and words used in the following description and claims are not limited to the dictionary meanings, but are merely used by the inventor to enable a clear and consistent understanding of the present disclosure. Accordingly, it should be apparent to those skilled in the art that the following description of various embodiments of the present disclosure is provided for illustration purpose only and not for the purpose of limiting the present disclosure as defined by the appended claims and their equivalents. 
     It is to be understood that the singular forms “a,” “an,” and “the” include plural referents unless the context clearly dictates otherwise. Thus, for example, reference to “a component surface” includes reference to one or more of such surfaces. 
     The expressions such as “include” and “may include” may denote the presence of the disclosed functions, operations, and constituent elements and do not limit one or more additional functions, operations, and constituent elements. Terms such as “include” and/or “have” may be construed to denote a certain characteristic, number, operation, constituent element, component or a combination thereof, but may not be construed to exclude the existence of or a possibility of addition of one or more other characteristics, numbers, operations, constituent elements, components or combinations thereof. 
     Furthermore, in the present disclosure, the expression “and/or” includes any and all combinations of the associated listed words. For example, the expression “A and/or B” may include A, may include B, or may include both A and B. 
     In the present disclosure, expressions including ordinal numbers, such as “first” and “second,” etc., may modify various elements. However, such elements are not limited by the above expressions. For example, the above expressions do not limit the sequence and/or importance of the elements. The above expressions are used merely for the purpose to distinguish an element from the other elements. For example, a first user device and a second user device indicate different user devices although both of them are user devices. For example, a first element could be termed a second element, and similarly, a second element could be also termed a first element without departing from the scope of the present disclosure. 
     In the case where a component is referred to as being “connected” or “accessed” to other component, it should be understood that not only the component is directly connected or accessed to the other component, but also there may exist another component between them. Meanwhile, in the case where a component is referred to as being “directly connected” or “directly accessed” to other component, it should be understood that there is no component therebetween. The terms used in the present disclosure are only used to describe specific various embodiments, and are not intended to limit the present disclosure. As used herein, the singular forms are intended to include the plural forms as well, unless the context clearly indicates otherwise. Singular forms are intended to include plural forms unless the context clearly indicates otherwise. 
     An electronic device according to the present disclosure may be a device including a communication function. For example, the device corresponds to a combination of at least one of a smartphone, a tablet Personal Computer (PC), a mobile phone, a video phone, an e-book reader, a desktop PC, a laptop PC, a netbook computer, a Personal Digital Assistant (PDA), a Portable Multimedia Player (PMP), a digital audio player, a mobile medical device, an electronic bracelet, an electronic necklace, an electronic accessory, a camera, a wearable device, an electronic clock, a wrist watch, home appliances (for example, an air-conditioner, vacuum, an oven, a microwave, a washing machine, an air cleaner, and the like), an artificial intelligence robot, a TeleVision (TV), a Digital Video Disk (DVD) player, an audio device, various medical devices (for example, Magnetic Resonance Angiography (MRA), Magnetic Resonance Imaging (MRI), Computed Tomography (CT), a scanning machine, a ultrasonic wave device, or the like), a navigation device, a Global Positioning System (GPS) receiver, an Event Data Recorder (EDR), a Flight Data Recorder (FDR), a set-top box, a TV box (for example, Samsung HomeSync™, Apple TV™, or Google TV™), an electronic dictionary, vehicle infotainment device, an electronic equipment for a ship (for example, navigation equipment for a ship, gyrocompass, or the like), avionics, a security device, electronic clothes, an electronic key, a camcorder, game consoles, a Head-Mounted Display (HMD), a flat panel display device, an electronic frame, an electronic album, furniture or a portion of a building/structure that includes a communication function, an electronic board, an electronic signature receiving device, a projector, and the like. It is obvious to those skilled in the art that the electronic device according to the present disclosure is not limited to the aforementioned devices. 
       FIG. 1  is a block diagram illustrating a configuration of an electronic device according to an embodiment of the present disclosure. 
     Referring to  FIG. 1 , the electronic device  101  may include a bus  110 , a processor  120 , a memory  130 , a input/output interface  150 , a display  160  and a communication interface  170 , and other similar and/or suitable components. 
     The bus  110  may be a circuit which interconnects the above-described elements and delivers a communication (e.g., a control message) between the above-described elements. 
     The processor  120  may receive commands from the above-described other elements (e.g., the memory  130 , input/output interface  150 , the display  160 , the communication interface  170 , etc.) through the bus  110 , may interpret the received commands, and may execute calculation or data processing according to the interpreted commands. The processor  120  may include a microprocessor or any suitable type of processing circuitry, such as one or more general-purpose processors (e.g., ARM-based processors), a Digital Signal Processor (DSP), a Programmable Logic Device (PLD), an Application-Specific Integrated Circuit (ASIC), a Field-Programmable Gate Array (FPGA), a Graphical Processing Unit (GPU), a video card controller, etc. In addition, it would be recognized that when a general purpose computer accesses code for implementing the processing shown herein, the execution of the code transforms the general purpose computer into a special purpose computer for executing the processing shown herein. Any of the functions and steps provided in the Figures may be implemented in hardware, software or a combination of both and may be performed in whole or in part within the programmed instructions of a computer. No claim element herein is to be construed under the provisions of 35 U.S.C. 112, sixth paragraph, unless the element is expressly recited using the phrase “means for.” In addition, an artisan understands and appreciates that a “processor” or “microprocessor” may be hardware in the claimed disclosure. Under the broadest reasonable interpretation, the appended claims are statutory subject matter in compliance with 35 U.S.C. §101. 
     The memory  130  may store commands or data received from the processor  120  or other elements (e.g., the input/output interface  150 , a display  160  and a communication interface  170 , etc.) or generated by the processor  120  or the other elements. The memory  130  may include programming modules, such as a kernel  131 , middleware  132 , an Application Programming Interface (API)  133 , an application  134 , and the like. Each of the above-described programming modules may be implemented in software, firmware, hardware, or a combination of two or more thereof. 
     The kernel  131  may control or manage system resources (e.g., the bus  110 , the processor  120 , the memory  130 , and/or other hardware and software resources) used to execute operations or functions implemented by other programming modules (e.g., the middleware  132 , the API  133 , and the application  134 ). Also, the kernel  131  may provide an interface capable of accessing and controlling or managing the individual elements of the electronic device  101  by using the middleware  132 , the API  133 , or the application  134 . 
     The middleware  132  may serve to go between the API  133  or the application  134  and the kernel  131  in such a manner that the API  133  or the application  134  communicates with the kernel  131  and exchanges data therewith. Also, in relation to work requests received from one or more applications  134  and/or the middleware  132 , for example, may perform load balancing of the work requests by using a method of assigning a priority, in which system resources (e.g., the bus  110 , the processor  120 , the memory  130 , etc.) of the electronic device  101  can be used, to at least one of the one or more applications  134 . 
     The API  133  is an interface through which the application  134  is capable of controlling a function provided by the kernel  131  or the middleware  132 , and may include, for example, at least one interface or function for file control, window control, image processing, character control, or the like. 
     The input/output interface  150 , for example, may receive a command or data as input from a user, and may deliver the received command or data to the processor  120  or the memory  130  through the bus  110 . The display module  160  may display a video, an image, data, or the like to the user. 
     The communication interface module  170  may connect communication between another electronic device  102  and the electronic device  101 . The communication interface module  170  may support a predetermined short-range communication protocol (e.g., Wi-Fi, BlueTooth (BT), and Near Field Communication (NFC)), or predetermined network  162  (e.g., the Internet, a Local Area Network (LAN), a Wide Area Network (WAN), a telecommunication network, a cellular network, a satellite network, a Plain Old Telephone Service (POTS), or the like). Each of the electronic devices  102  and  104  may be a device which is identical (e.g., of an identical type) to or different (e.g., of a different type) from the electronic device  101 . Further, the communication interface module  170  may connect communication between a server  164  and the electronic device  101  via the network  162 . 
       FIG. 2  is a block diagram illustrating a configuration of an electronic device  201  according to an embodiment of the present disclosure. 
     The hardware shown in  FIG. 2  may be, for example, the electronic device  101  illustrated in  FIG. 1 . 
     Referring to  FIG. 2 , the electronic device may include one or more processors  210 , a communication module  220 , a Subscriber Identification Module (SIM) card  224 , a memory  230 , a sensor module  240 , a input device  250 , a display module  260 , an interface  270 , an audio module  280 , a camera module  291 , a power management module  295 , a battery  296 , an indicator  297 , a motor  298  and any other similar and/or suitable components. 
     The Application Processor (AP)  210  (e.g., the processor  120 ) may include one or more Application Processors (APs), or one or more Communication Processors (CPs). The processor  210  may be, for example, the processor  120  illustrated in  FIG. 1 . The AP  210  is illustrated as being included in the processor  210  in  FIG. 2 , but may be included in different Integrated Circuit (IC) packages, respectively. According to an embodiment of the present disclosure, the AP  210  may be included in one IC package. 
     The AP  210  may execute an Operating System (OS) or an application program, and thereby may control multiple hardware or software elements connected to the AP  210  and may perform processing of and arithmetic operations on various data including multimedia data. The AP  210  may be implemented by, for example, a System on Chip (SoC). According to an embodiment of the present disclosure, the AP  210  may further include a Graphical Processing Unit (GPU) (not illustrated). 
     The AP  210  may manage a data line and may convert a communication protocol in the case of communication between the electronic device (e.g., the electronic device  101 ) including the hardware and different electronic devices connected to the electronic device through the network. The AP  210  may be implemented by, for example, a SoC. According to an embodiment of the present disclosure, the AP  210  may perform at least some of multimedia control functions. The AP  210 , for example, may distinguish and authenticate a terminal in a communication network by using a subscriber identification module (e.g., the SIM card  224 ). Also, the AP  210  may provide the user with services, such as a voice telephony call, a video telephony call, a text message, packet data, and the like. 
     Further, the AP  210  may control the transmission and reception of data by the communication module  220 . In  FIG. 2 , the elements such as the AP  210 , the power management module  295 , the memory  230 , and the like are illustrated as elements separate from the AP  210 . However, according to an embodiment of the present disclosure, the AP  210  may include at least some (e.g., the CP) of the above-described elements. 
     According to an embodiment of the present disclosure, the AP  210  may load, to a volatile memory, a command or data received from at least one of a non-volatile memory and other elements connected to each of the AP  210 , and may process the loaded command or data. Also, the AP  210  may store, in a non-volatile memory, data received from or generated by at least one of the other elements. 
     The SIM card  224  may be a card implementing a subscriber identification module, and may be inserted into a slot formed in a particular portion of the electronic device  101 . The SIM card  224  may include unique identification information (e.g., Integrated Circuit Card IDentifier (ICCID)) or subscriber information (e.g., International Mobile Subscriber Identity (IMSI)). 
     The memory  230  may include an internal memory  232  and an external memory  234 . The memory  230  may be, for example, the memory  130  illustrated in  FIG. 1 . The internal memory  232  may include, for example, at least one of a volatile memory (e.g., a Dynamic RAM (DRAM), a Static RAM (SRAM), a Synchronous Dynamic RAM (SDRAM), etc.), and a non-volatile memory (e.g., a One Time Programmable ROM (OTPROM), a Programmable ROM (PROM), an Erasable and Programmable ROM (EPROM), an Electrically Erasable and Programmable ROM (EEPROM), a mask ROM, a flash ROM, a Not AND (NAND) flash memory, a Not OR (NOR) flash memory, etc.). According to an embodiment of the present disclosure, the internal memory  232  may be in the form of a Solid State Drive (SSD). The external memory  234  may further include a flash drive, for example, a Compact Flash (CF), a Secure Digital (SD), a Micro-Secure Digital (Micro-SD), a Mini-Secure Digital (Mini-SD), an extreme Digital (xD), a memory stick, or the like. 
     The communication module  220  may include a cellular module  221 , a wireless (WiFi) communication module  223  or a Radio Frequency (RF) module  229 . The communication module  220  may be, for example, the communication interface  170  illustrated in  FIG. 1 . The communication module  220  may include, for example, a Wi-Fi part  223 , a BT part  225 , a GPS part  227 , or a NFC part  229 . For example, the wireless communication module  220  may provide a wireless communication function by using a radio frequency. Additionally or alternatively, the wireless communication module  220  may include a network interface (e.g., a LAN card), a modulator/demodulator (modem), or the like for connecting the hardware to a network (e.g., the Internet, a LAN, a WAN, a telecommunication network, a cellular network, a satellite network, a POTS, or the like). 
     The RF module  229  may be used for transmission and reception of data, for example, transmission and reception of RF signals or called electronic signals. Although not illustrated, the RF unit  229  may include, for example, a transceiver, a Power Amplifier Module (PAM), a frequency filter, a Low Noise Amplifier (LNA), or the like. Also, the RF module  229  may further include a component for transmitting and receiving electromagnetic waves in a free space in a wireless communication, for example, a conductor, a conductive wire, or the like. 
     The sensor module  240  may include, for example, at least one of a gesture sensor  240 A, a gyro sensor  240 B, an barometer sensor  240 C, a magnetic sensor  240 D, an acceleration sensor  240 E, a grip sensor  240 F, a proximity sensor  240 G, a Red, Green and Blue (RGB) sensor  240 H, a biometric sensor  240 I, a temperature/humidity sensor  240 J, an illuminance sensor  240 K, and a Ultra Violet (UV) sensor  240 M. The sensor module  240  may measure a physical quantity or may sense an operating state of the electronic device  101 , and may convert the measured or sensed information to an electrical signal. Additionally/alternatively, the sensor module  240  may include, for example, an E-nose sensor (not illustrated), an ElectroMyoGraphy (EMG) sensor (not illustrated), an ElectroEncephaloGram (EEG) sensor (not illustrated), an ElectroCardioGram (ECG) sensor (not illustrated), a fingerprint sensor (not illustrated), and the like. Additionally or alternatively, the sensor module  240  may include, for example, an E-nose sensor (not illustrated), an EMG sensor (not illustrated), an EEG sensor (not illustrated), an ECG sensor (not illustrated), a fingerprint sensor, and the like. The sensor module  240  may further include a control circuit (not illustrated) for controlling one or more sensors included therein. 
     The input device  250  may include a touch panel  252 , a pen sensor  254  (e.g., a digital pen sensor), keys  256 , and an ultrasonic input unit  258 . The input device  250  may be, for example, the input/output interface  150  illustrated in  FIG. 1 . The touch panel  252  may recognize a touch input in at least one of, for example, a capacitive scheme, a resistive scheme, an infrared scheme, and an acoustic wave scheme. Also, the touch panel  252  may further include a controller (not illustrated). In the capacitive type, the touch panel  252  is capable of recognizing proximity as well as a direct touch. The touch panel  252  may further include a tactile layer (not illustrated). In this event, the touch panel  252  may provide a tactile response to the user. 
     The pen sensor  254  (e.g., a digital pen sensor), for example, may be implemented by using a method identical or similar to a method of receiving a touch input from the user, or by using a separate sheet for recognition. For example, a key pad or a touch key may be used as the keys  256 . The ultrasonic input unit  258  enables the terminal to sense a sound wave by using a microphone (e.g., a microphone  288 ) of the terminal through a pen generating an ultrasonic signal, and to identify data. The ultrasonic input unit  258  is capable of wireless recognition. According to an embodiment of the present disclosure, the hardware may receive a user input from an external device (e.g., a network, a computer, or a server), which is connected to the communication module  220 , through the communication module  220 . 
     The display module  260  may include a panel  262 , a hologram  264 , or projector  266 . The display module  260  may be, for example, the display module  160  illustrated in  FIG. 1 . The panel  262  may be, for example, a Liquid Crystal Display (LCD) and an Active Matrix Organic Light Emitting Diode (AM-OLED) display, and the like. The panel  262  may be implemented so as to be, for example, flexible, transparent, or wearable. The panel  262  may include the touch panel  252  and one module. The hologram  264  may display a three-dimensional image in the air by using interference of light. According to an embodiment of the present disclosure, the display module  260  may further include a control circuit for controlling the panel  262  or the hologram  264 . 
     The interface  270  may include, for example, a High-Definition Multimedia Interface (HDMI)  272 , a Universal Serial Bus (USB)  274 , an optical interface  276 , and a D-subminiature (D-sub)  278 . Additionally or alternatively, the interface  270  may include, for example, SD/Multi-Media Card (MMC) (not illustrated) or Infrared Data Association (IrDA) (not illustrated). 
     The audio codec  280  may bidirectionally convert between a voice and an electrical signal. The audio codec  280  may convert voice information, which is input to or output from the audio codec  280 , through, for example, a speaker  282 , a receiver  284 , an earphone  286 , the microphone  288  or the like. 
     The camera module  291  may capture an image and a moving image. According to an embodiment, the camera module  291  may include one or more image sensors (e.g., a front lens or a back lens), an Image Signal Processor (ISP) (not illustrated), and a flash LED (not illustrated). 
     The power management module  295  may manage power of the hardware. Although not illustrated, the power management module  295  may include, for example, a Power Management Integrated Circuit (PMIC), a charger Integrated Circuit (IC), or a battery fuel gauge. 
     The PMIC may be mounted to, for example, an IC or a SoC semiconductor. Charging methods may be classified into a wired charging method and a wireless charging method. The charger IC may charge a battery, and may prevent an overvoltage or an overcurrent from a charger to the battery. According to an embodiment of the present disclosure, the charger IC may include a charger IC for at least one of the wired charging method and the wireless charging method. Examples of the wireless charging method may include a magnetic resonance method, a magnetic induction method, an electromagnetic method, and the like. Additional circuits (e.g., a coil loop, a resonance circuit, a rectifier, etc.) for wireless charging may be added in order to perform the wireless charging. 
     The battery fuel gauge may measure, for example, a residual quantity of the battery  296 , or a voltage, a current or a temperature during the charging. The battery  296  may supply power by generating electricity, and may be, for example, a rechargeable battery. 
     The indicator  297  may indicate particular states of the hardware or a part (e.g., the AP  211 ) of the hardware, for example, a booting state, a message state, a charging state and the like. The motor  298  may convert an electrical signal into a mechanical vibration. The processor  210  may control the sensor module  240 . 
     Although not illustrated, the hardware may include a processing unit (e.g., a GPU) for supporting a module TV. The processing unit for supporting a module TV may process media data according to standards such as, for example, Digital Multimedia Broadcasting (DMB), Digital Video Broadcasting (DVB), media flow, and the like. Each of the above-described elements of the hardware according to an embodiment of the present disclosure may include one or more components, and the name of the relevant element may change depending on the type of electronic device. The hardware according to an embodiment of the present disclosure may include at least one of the above-described elements. Some of the above-described elements may be omitted from the hardware, or the hardware may further include additional elements. Also, some of the elements of the hardware according to an embodiment of the present disclosure may be combined into one entity, which may perform functions identical to those of the relevant elements before the combination. 
     The term “module” used in the present disclosure may refer to, for example, a unit including one or more combinations of hardware, software, and firmware. The “module” may be interchangeable with a term, such as “unit,” “logic,” “logical block,” “component,” “circuit,” or the like. The “module” may be a minimum unit of a component formed as one body or a part thereof. The “module” may be a minimum unit for performing one or more functions or a part thereof. The “module” may be implemented mechanically or electronically. For example, the “module” according to an embodiment of the present disclosure may include at least one of an Application-Specific Integrated Circuit (ASIC) chip, a Field-Programmable Gate Array (FPGA), and a programmable-logic device for performing certain operations which have been known or are to be developed in the future. 
       FIG. 3  is a block diagram illustrating a configuration of one or more programming modules  300  according to an embodiment of the present disclosure. 
     The programming module  300  may be included (or stored) in the electronic device  101  (e.g., the memory  130 ) or may be included (or stored) in the electronic device  201  (e.g., the memory  230 ) illustrated in  FIG. 1 . At least a part of the programming module  300  may be implemented in software, firmware, hardware, or a combination of two or more thereof. The programming module  300  may be implemented in hardware (e.g., the hardware), and may include an OS controlling resources related to an electronic device (e.g., the electronic device  101 ) and/or various applications (e.g., an application  370 ) executed in the OS. For example, the OS may be Android, iOS, Windows, Symbian, Tizen, Bada, and the like. 
     Referring to  FIG. 3 , the programming module  300  may include a kernel  310 , a middleware  330 , an API  360 , and/or the application  370 . 
     The kernel  310  (e.g., the kernel  131 ) may include a system resource manager  311  and/or a device driver  312 . The system resource manager  311  may include, for example, a process manager (not illustrated), a memory manager (not illustrated), and a file system manager (not illustrated). The system resource manager  311  may perform the control, allocation, recovery, and/or the like of system resources. The device driver  312  may include, for example, a display driver (not illustrated), a camera driver (not illustrated), a Bluetooth driver (not illustrated), a shared memory driver (not illustrated), a USB driver (not illustrated), a keypad driver (not illustrated), a Wi-Fi driver (not illustrated), and/or an audio driver (not illustrated). Also, according to an embodiment of the present disclosure, the device driver  312  may include an Inter-Process Communication (IPC) driver (not illustrated). 
     The middleware  330  may include multiple modules previously implemented so as to provide a function used in common by the applications  370 . Also, the middleware  330  may provide a function to the applications  370  through the API  360  in order to enable the applications  370  to efficiently use limited system resources within the electronic device. For example, as illustrated in  FIG. 3 , the middleware  330  (e.g., the middleware  132 ) may include at least one of a runtime library  335 , an application manager  341 , a window manager  342 , a multimedia manager  343 , a resource manager  344 , a power manager  345 , a database manager  346 , a package manager  347 , a connectivity manager  348 , a notification manager  349 , a location manager  350 , a graphic manager  351 , a security manager  352 , and any other suitable and/or similar manager. 
     The runtime library  335  may include, for example, a library module used by a complier, in order to add a new function by using a programming language during the execution of the application  370 . According to an embodiment of the present disclosure, the runtime library  335  may perform functions which are related to input and output, the management of a memory, an arithmetic function, and/or the like. 
     The application manager  341  may manage, for example, a life cycle of at least one of the applications  370 . The window manager  342  may manage GUI resources used on the screen. The multimedia manager  343  may detect a format used to reproduce various media files and may encode or decode a media file through a codec appropriate for the relevant format. The resource manager  344  may manage resources, such as a source code, a memory, a storage space, and/or the like of at least one of the applications  370 . 
     The power manager  345  may operate together with a Basic Input/Output System (BIOS), may manage a battery or power, and may provide power information and the like used for an operation. The database manager  346  may manage a database in such a manner as to enable the generation, search and/or change of the database to be used by at least one of the applications  370 . The package manager  347  may manage the installation and/or update of an application distributed in the form of a package file. 
     The connectivity manager  348  may manage a wireless connectivity such as, for example, Wi-Fi and Bluetooth. The notification manager  349  may display or report, to the user, an event such as an arrival message, an appointment, a proximity alarm, and the like in such a manner as not to disturb the user. The location manager  350  may manage location information of the electronic device. The graphic manager  351  may manage a graphic effect, which is to be provided to the user, and/or a user interface related to the graphic effect. The security manager  352  may provide various security functions used for system security, user authentication, and the like. According to an embodiment of the present disclosure, when the electronic device (e.g., the electronic device  101 ) has a telephone function, the middleware  330  may further include a telephony manager (not illustrated) for managing a voice telephony call function and/or a video telephony call function of the electronic device. 
     The middleware  330  may generate and use a new middleware module through various functional combinations of the above-described internal element modules. The middleware  330  may provide modules specialized according to types of OSs in order to provide differentiated functions. Also, the middleware  330  may dynamically delete some of the existing elements, or may add new elements. Accordingly, the middleware  330  may omit some of the elements described in the various embodiments of the present disclosure, may further include other elements, or may replace the some of the elements with elements, each of which performs a similar function and has a different name. 
     The API  360  (e.g., the API  133 ) is a set of API programming functions, and may be provided with a different configuration according to an OS. In the case of Android or iOS, for example, one API set may be provided to each platform. In the case of Tizen, for example, two or more API sets may be provided to each platform. 
     The applications  370  (e.g., the applications  134 ) may include, for example, a preloaded application and/or a third party application. The applications  370  (e.g., the applications  134 ) may include, for example, a home application  371 , a dialer application  372 , a Short Message Service (SMS)/Multimedia Message Service (MMS) application  373 , an Instant Message (IM) application  374 , a browser application  375 , a camera application  376 , an alarm application  377 , a contact application  378 , a voice dial application  379 , an electronic mail (e-mail) application  380 , a calendar application  381 , a media player application  382 , an album application  383 , a clock application  384 , and any other suitable and/or similar application. 
     At least a part of the programming module  300  may be implemented by instructions stored in a non-transitory computer-readable storage medium. When the instructions are executed by one or more processors (e.g., the one or more processors  210 ), the one or more processors may perform functions corresponding to the instructions. The non-transitory computer-readable storage medium may be, for example, the memory  230 . At least a part of the programming module  300  may be implemented (e.g., executed) by, for example, the one or more processors  210 . At least a part of the programming module  300  may include, for example, a module, a program, a routine, a set of instructions, and/or a process for performing one or more functions. 
     Names of the elements of the programming module (e.g., the programming module  300 ) according to an embodiment of the present disclosure may change depending on the type of OS. The programming module according to an embodiment of the present disclosure may include one or more of the above-described elements. Alternatively, some of the above-described elements may be omitted from the programming module. Alternatively, the programming module may further include additional elements. The operations performed by the programming module or other elements according to an embodiment of the present disclosure may be processed in a sequential method, a parallel method, a repetitive method, or a heuristic method. Also, some of the operations may be omitted, or other operations may be added to the operations. 
       FIG. 4  is a block diagram showing a network environment  400  including electronic device  410  according to one embodiment of the present disclosure. 
     With reference to  FIG. 4 , the network environment  400  may be configured to be similar or identical to the network environment  100  shown in  FIG. 1 . The electronic device  410  may be configured to be similar or identical to the electronic device  101  shown in  FIG. 1 . The electronic device  410  is capable of connecting to a server  420  (e.g., server  106 ), and external devices  440  and  450  (e.g., the electronic device  102  and the electronic device  104 ) via the network  430  in the network environment  400 . In the embodiment, the external devices  440  and  450  refer to devices which are owned by other users or parties and include a communication module with a call function. Examples of external devices  440  and  450  may include mobile phones known in the art. 
     In the network environment  400  configured as described above, a call service providing method according to the present disclosure allows a user of the electronic device  410  to initiate a second call with a second party while connected to a first call with a first party, so that the user can make calls with a number of parties simultaneously. To this end, the electronic device  410  maintains the existing call in a voice call mode via the first communication network  432  of the network  430  and may initiate the new call in a text-speech conversion mode via the second communication network  434  of the network  430 . 
     The first communication network  432  may be a circuit switching (CS) network providing a voice call service. The second communication network  434  may be a packet switching (PS) network providing a data transmission/reception service. In another embodiment, the first communication network  432  and second communication network  434  may be first and second channels in the same communication network. 
     In particular, the electronic device  410  converts a text message input by the user into a speech message (TTS service) and transmits the speech message to the network  430  (e.g., network  162 ). The electronic device  410  also converts a speech message, received from the second party via the network  430 , into a text message (STT service), and provides the text message to the user. In various embodiments, the conversion between text and speech (TTS service and STT service) may be independently performed by the electronic device  410  or performed by the electronic device  410  in further cooperation with the server  420 . The following description is described based on the conversion between text and speech (TTS service and STT service) which is independently performed by the electronic device  410 . However, it should be understood that the present disclosure is not limited thereto. 
       FIG. 5  is a detailed block diagram of an electronic device  410  according to one embodiment of the present disclosure. 
     With reference to  FIG. 5 , the electronic device  410  (e.g., electronic device  101 ) may include a control circuit  510 , a communication module  520 , a memory  530 , a display unit  540 , an audio module  550 , and an input device  560 . 
     The control circuit  510  (e.g., processor  120 ) may include a call control module  512 , a TTS module  514 , and an STT module  516 . The control circuit  510  may include part or all of an application processor (AP) and/or software programs stored in the memory. 
     The call control module  512  controls the call function of the electronic device  410 . The call control module  512  controls the communication module  520  to initiate and connect one or more calls to specified parties according to a user&#39;s request. The call control module  512  may also detect that the user has received a request to connect a call from a second party during a call with a first party, and provides the user with a call service in a text-speech conversion mode. When the call control module  512  receives a third call request of a third party, it is capable of providing the user with a call service in a speech-text conversion mode for the third call. To this end, the call control module  512  is capable of controlling the TTS module  514  and the STT module  516 . The call control module  512  may detect a communication network or channel that the electronic device  410  is currently using, and also additionally other available communication networks or channels. Therefore, the electronic device  410  is capable of making a new call (e.g., a call in a text-speech conversion mode) via one of the other available communication networks or channels other than the communication network/channel currently in use for the existing call. 
     The call control module  512  controls the call service in a text-speech conversion mode according to a user&#39;s request. The call control module  512  provides the TTS module  514  with text input by the user or text data received from the external electronic device, and controls the TTS module  514  to convert the text or text data into voice signals. The call control module  512  also provides the voice signals converted by the TTS module  514  to either the external electronic device via the communication module  520  or to the user via the speaker (e.g. the audio module  550 ). In another embodiment, transmission of the voice signals may be performed by the TTS module  514 . 
     The call control module  512  also controls the call service in a speech-text conversion mode according to a user&#39;s request. The call control module  512  transfers voice signals, provided by the speaker or received from the external electronic device, to the STT module  516  and controls the STT module  516  to convert the voice signals into text data based on a speech recognition database. The call control module  512  provides text converted by the STT module  516  to either the external electronic device via the communication module  520  or to the user via the display unit  540 . In another embodiment, transmission of the text data may be performed by the STT module  516 . 
     The TTS module  514  converts text into voice signals. In one embodiment, the TTS module  514  converts text into voice signals by creating voice signals based on the text. To this end, the TTS module  514  manages and operates a database which includes text information corresponding to languages and speech information. In one embodiment, the TTS module  514  may collect voice-related features of received voice signals, including pitch, tone, voice features, etc., and applies the collected voice-related features to the voice signals it generates. That is, when the TTS module  514  converts text into a voice signal, it collects voice-related features of the user&#39;s voice, and creates a voice signal similar to the user&#39;s voice in terms of pitch, tone, etc. To this end, the TTS module  514  may include components for adjusting voice features, such as pitch, tone, etc. to create voice signals of various timbres. For example, the TTS module  514  is capable of creating voice signals corresponding to the user&#39;s gender. The TTS module  514  is also capable of controlling the creation of voice signals corresponding to the user&#39;s voice tones, e.g., high tone, low tone, etc. In another embodiment, when the function of converting text into voice signals is designed to be performed by a separate TTS server, the TTS module  514  is capable of connecting to the TTS server via the communication module  520 , providing text data to the server, and receiving corresponding voice signals from the server. 
     The STT module  516  performs the speech recognition for voice signals provided by the call control module  512  and creates text data from the voice signals. To this end, the STT module  516  is capable of operating a speech recognition database and performing the speech recognition for voice signals based on the database. In one embodiment, when a speech recognition for text data generation is designed to be performed in conjunction with a separate automatic speech recognition (ASR) server, the STT module  516  is capable of connecting to the ASR server via the communication module  520 , providing voice signals to the server, and receiving corresponding text information from the server. 
     The communication module  520  (e.g., communication interface  170 ) is capable of establishing a data communication channel with another electronic device via the network environment  400 . The communication module  520  may be configured to support various communication modes according to characteristics of electronic device  410 . For example, the communication module  520  may be a mobile communication module capable of supporting 2G, 3G, 4G, etc., a communication module capable of supporting WiFi, etc. In particular, the communication module  520  is capable of establishing a data communication channel for performing the transmission/reception of text data with the other electronic device according to user input, while simultaneously maintaining a voice communication connection with a third electronic device. In one embodiment, the data communication channel is used to transmit at least one of the following: text data created via the speech recognition, voice signals, videos, text input via the input device  560 , etc. 
     The memory  530  (e.g., memory  130 ) is capable of storing an operating system of the electronic device  410 , application programs for supporting various functions of the electronic device, etc. In particular, the memory  530  is capable of storing application programs for supporting a TTS service and an STT service, a speech recognition database  532  for supporting the speech recognition, a speech conversion database  534 , etc. 
     When the electronic device  410  is designed to perform the speech recognition, the speech recognition database  532 , locally stored in memory  530  is capable of supporting the speech recognition function. Although the local speech recognition database  532  may have a relatively low level of reliability and a relatively slow operating speed for the speech recognition result, compared with the ASR server, it is capable of supporting a speech recognition customized to the user of the electronic device  410 . That is, the speech recognition database  532  stores a speech recognition history of voice signals input by the user, and includes results that match the user&#39;s voice signals and previously stored voice patterns and texts. Therefore, the speech recognition database storing data internally by itself is capable of supporting the speech recognition function and may be customized to the particular user of the electronic device, unlike the ASR server, which is not customized to this particular user because the ASR server serves a multitude of devices. To this end, the speech recognition database  532  is capable of providing a learning function, under the control of the control circuit  510 . The learning function is performed in such a way that, when matching a voice signal input by the particular user of this electronic device with a text result, when an event for adjusting the voice signal to the text result occurs due to a user input, such as a correction, etc., the event is recorded and applied to subsequent speech recognition results. The learning function thereby increases the accuracy of the speech recognition result for voice signals of the user of the electronic device. 
     The speech conversion database  534  stores audio patterns of words, phrases, postposition/preposition/suffix/prefix, sentences, etc., so that when text is input, voice signals corresponding to the text input is generated. The speech conversion database  534  may be used to support a TTS service. In particular, the speech conversion database  534  may include a database created by matching text corresponding to one or more languages with voice signals corresponding to the text. 
     The display unit  540  (e.g., display  160 ) is capable of providing various screen interfaces required to operate the electronic device  410 . The display unit  540  may be configured to include a display panel and a touch panel for supporting a touch sensing function. The display unit  540  is capable of providing screens according to types of communication services provided by the electronic device. For example, the display unit  540  is capable of outputting at least one of the following: a screen for supporting a voice call, a screen for supporting a call service in a text-speech conversion mode, and a screen for supporting a video call service. 
     The audio module  550  (e.g., audio module  280 ) includes a microphone and a speaker. 
     The microphone (e.g., microphone  288 ) is activated according to the activated functions of the electronic device  410  and collects the ambient audio signals, such as voice signals. The microphone transfers the collected voice signals to the control circuit  510 . The control circuit  510 , as explained above, converts the voice signals into text and transmits the text data via the communication module  520 . In one embodiment, the voice signals are encoded according to the data transfer protocol, and transmitted to the speech recognition server via the communication module  520 . The speech recognition server converts the voice signals into a text message and transmits the text message back to the electronic device  410  or to another electronic device (e.g. a counter party in a call). 
     The speaker (e.g., speaker  282 ) outputs audio signals of the electronic device  410 . The speaker outputs audio data according to the playback of audio files which are stored in the electronic device  410  or received from an external server or another electronic device. When the electronic device receives a text message, a video, or the like from another electronic device (e.g. a counter party in a call), the speaker outputs a corresponding notification sound or ring tone. In one embodiment, the speaker is capable of outputting a notification sound according to an STT service converting text to a speech, under the control of the control circuit  510 . 
     The input device  560  (e.g., input device  250 ) is capable of creating various input signals required to operate the electronic device  410 . The input device  560  may be implemented in a form of specified keys, such as button keys, side keys, a home key, etc. Alternatively, the input device  560  may further be implemented with a virtual touch pad supported by a touch screen implemented in the display unit  540 . The virtual touch pad may be configured to be displayed on the display unit  540  and create events corresponding to a user&#39;s touch inputs. The input device  560  is capable of creating: an input signal for connecting to a receiver with a communication service, an input signal for operating the communication service, an input signal for the input of text, an input signal for activating another communication service while providing a specified communication service, etc., according to a user&#39;s controls. The control circuit  510  receives the created input signal and supports a function corresponding to the input signal. 
     In an embodiment, an electronic device is implemented to include: at least one communication circuit supporting at least one communication protocol; a display; a microphone; a speaker; an input device which is configured with or separated from the display; a control circuit electrically coupled to the communication circuit, the display, the microphone, the speaker, and the input device; and a memory electrically coupled to the control circuit. The memory stores instructions executable by the control circuit to: receive a first call from a first external electronic device via the at least one communication circuit; during the first call, receive a request for a second call from a second external electronic device via the at least one communication circuit; receive the second call based on input via the input device; convert a first voice data from the second external electronic device to a first text data and display the first text data on the display; and convert a second text data inputted via the input device to a second voice data and transmit the second voice data to the second external electronic device. 
     In an embodiment, an electronic device is completed to include: a communication module; and a control circuit. The control circuit is configured to: receive a request for a second call from a second party while the electronic device is connected with a first party in a first call; and control the communication module to connect the second call with the second party while maintaining the first call, according to an input from a user of the electronic device, wherein the first call is connected in a first communication mode and the second call is connected in a second communication mode. The first communication mode is a voice communication mode and the second communication mode is a hybrid voice and text communication mode wherein a first voice data from the second party is converted to a first text data to be displayed on a display, and a second text data inputted by the user of the electronic device is converted to a second voice data and transmitted to the second party. In the second communication mode, the user of the electronic device performs the second call with the second party in a form of text conversation and the second party performs the second call with the user in a form of voice conversation. The control circuit further: after receiving the request for the second call from the second party during the first call, receive user input to accept the second call in the second communication mode; and connect the second call in the second communication mode based on the received user input. The control circuit includes: a speech-to-text (STT) module adapted to convert the first voice data from the second party to the first text data; and a text-to-speech (TTS) module adapted to convert the second text data inputted by the user of the electronic device to the second voice data. The control circuit is further configured to: request a third call to a third party according to input by the user; receive, from the third party, a request to connect the third call in a third communication mode; request confirmation from the user to connect the third call in the third communication mode; and when confirmation from the user is received, connect the third call in the third communication mode. In the third communication mode, the user of the electronic device performs the third call with the third party in a form of voice conversation and the third party performs the third call with the user in a form of text conversation. The STT module converts the third voice data from the user of the electronic device to the third text data and transmits the third text data to the third party during the third call. The TTS module converts the fourth text data from the third party to the fourth voice data and outputs the fourth voice data to the user during the third call. Before connecting the second or third call, the control circuit controls the communication module to register contacts of the user in a first server; receive a token from the first server; and transmits the token to a second server. The control circuit is further configured to: create a group of contacts when the user accepts the second call, the group of contacts include the first party and the second party; create a group identification (ID) corresponding to the created group; transmit the group ID to the second server; and connect the second call and merge the first call and the second call when the first party and the second party accepts participation in the group. The control circuit is further configured to: receive a group ID corresponding to a group of contacts created by the third party from the first server when the user accepts the third call; transmit a request to participate in the group to the second server; and connect the third call. The first call is connected via a first communication network and the second call is connected via a second communication network, the first communication network is a circuit switching (CS) network providing a voice call service; and the second communication network is a packet switching (PS) network providing a data transmission/reception service. 
     The following description provides a call service providing method of an electronic device according to one or more embodiments of the present disclosure. 
       FIG. 6  is a flowchart that describes a call service providing method of an electronic device according to an embodiment of the present disclosure.  FIG. 7  is a flow diagram that describes a method of simultaneously performing first and second calls according to one embodiment of the present disclosure.  FIGS. 6 and 7  are flowcharts that describe the call service providing method of the electronic device  410  when the user of the electronic device  410  attempts to make a call to a second party while connected to a call with a first party. 
     The control circuit  510  is capable of controlling the communication module  520  and the audio module  550  to connect the user to the first call function with the first party in operation  610 . 
     For example, the user of the electronic device may be listening to music using a hands-free accessory before being connected to the call to the first party. When the user receives a request for the call from the first party, he/she may be connected to the first call with the first party using the hands-free accessory. The first call may be in the voice call mode between the user and the first party. That is, both the user and the first party communicate by speaking into their respective electronic devices and hear the responses from each other. The first call may be connected via a first communication network, e.g., a circuit switching (CS) network. Alternatively, the first call may be connected via a second communication network, e.g., a packet switching (PS) network. Or the first call may be connected via a first channel in the first communication network. It should be understood that the first call may also be connected via any other types of communication network. 
     The control circuit  510  recognizes that a request for a second call has been received from a second party in operation  620 . 
     The control circuit  510  notifies the user that the request for the second call has been received from a second party, and controls the display unit  540  to display a confirmation request asking the user whether he/she wishes to connect to the second call with the second party in a mode that differs from that of the first call in operation  630 . For example, the second call may be connected in such a way that the user performs the second call with the second party in the form of text conversation and the second party performs the second call with the user in the form of voice conversation. Therefore, the confirmation request may be a message asking the user whether he/she accepts the second call with the second party in a text-speech conversion mode. The control circuit  510  controls the audio module  550  to output an audio message or a haptic module to output a vibration signal. When the user receives the audio message or the vibration signal, the user may connect the second call with the second party in a text-speech conversion mode. 
     The control circuit  510  is capable of simultaneously performing first and second calls according to a user&#39;s second call request in operation  640 . To this end, when the control circuit  510  controls the communication module  520  to connect the second call and receives information that the second party has accepted the second call, it controls the communication module  520  to connect the first and second calls simultaneously. 
     Then for the second call, the call control module  512  of the control circuit  510  controls the TTS module  514  to convert text that the user input via the input device  560  into a voice signal, and transmits the converted voice signal to the electronic device of the second party via the second communication network. In another embodiment, the control circuit  510  or the TTS module  514  transmits the converted voice signal to the electronic device of the second party via a second communication channel of the first communication network. 
     The call control module  512  of the control circuit  510  controls the STT module  516  to convert voice data received from the second party, into text. The control circuit  510  or the STT module  516  can then cause the converted text to be displayed on the display unit  540 . According to one embodiment of the present disclosure, the process of performing first and second calls may further include operations  710  to  730  as shown in  FIG. 7 . 
     The control circuit  510  is capable of creating a group of contacts and a group identification (ID) corresponding to the created group, according to a user&#39;s request in operation  710 . The group may include the first party of the first call and the second party of the second call. The group is used to establish a channel through which the user makes a second call with the second party. Information regarding the group and the group ID is transmitted to the electronic devices of the first and second parties via a server. When the first party and the second party accepts participation in the group, the second call is connected and the first call and the second call are merged in a specified communication network or channel. The specified communication network/channel may be identical to or different from the communication network/channel that the user is currently using for the first call. 
     The control circuit  510  controls the communication module  520  to transmit the created group ID to the server  420  in operation  720 . In this case, the server  420  is capable of transmitting the received group ID to the electronic device of the second party. 
     When a channel is established in the second communication network or a second channel in the first communication network is established, the control circuit  510  activates a second call in operation  730  and merges the first and second calls. The establishment of a channel in the second communication network or a second channel in the first communication network includes transmitting the group ID to the electronic device of the second party, and receiving a confirmation from the second party to participate in the group. 
       FIG. 8  is a flowchart that describes a call service providing method of an electronic device according to an embodiment of the present disclosure.  FIG. 9  is a flow diagram that describes a method of performing a third call according to one embodiment of the present disclosure.  FIGS. 8 and 9  are flowcharts that describe a call service providing method of an electronic device  410  when a user of the electronic device  410  attempts to initiate a call to a third party who is currently connected to another call. 
     The control circuit  510  attempts to connect a third call to a third party according to the user&#39;s request in operation  810 . 
     The control circuit  510  receives a third call request of the third party in operation  820 . For example, although the user wants to use a voice call with the third party, the third party is currently on a call with another party and may thus propose the third call with the user to be in the speech-text conversion mode. 
     The control circuit  510  shows a confirmation request asking the user whether he/she accepts the third call proposed by the third party in operation  830 . The control circuit  510  is capable of informing the user that the third party has proposed the third call, which will not be in the normal voice call mode. The confirmation request may be a message asking the user whether he/she accepts the third call with the third party in the speech-text conversion mode. For the confirmation, the control circuit  510  may controls the audio module  550  to output an audio message or control a haptic module to output a vibration signal. 
     If confirmed by the user, the control circuit  510  is capable of performing the third call according to a user&#39;s request in operation  840 . The STT module is capable of converting a speech input by the user into text data and outputting the converted text data during the third call. The call control module  512  of the control circuit  510  is capable of controlling the STT module  516  to convert a speech input by the user into text data and output the converted text data. The call control module  512  is also capable of controlling the TTS module  514  to convert text data received from the third party into speech and provide the speech to the user via a speaker. 
     According to one embodiment of the present disclosure, the process of performing a call may further include operations  910  and  920  as shown in  FIG. 9 . 
     The control circuit  510  is capable of receiving a group ID from the server  420  in operation  910 . The group ID is an ID of a group created by the third user and is transmitted from the device of the third user to the server  420 . 
     The control circuit  510  requests the server  420  to participate in the group and thus establishes a channel in the second communication network or a second channel in the first communication network in operation  920 . When the channel is established, the user is connected to the third call to the third party in a speech-text conversion mode. The third party may merge the third call with the call he/she was connected to prior to the initiation of the third call. The third call is performed in such a way that the user performs the third call with the third party in the form of voice conversation and the third party performs the third call with the user in the form of text conversation. 
       FIG. 10  is a flowchart that describes a call service providing method of an electronic device according to an embodiment of the present disclosure. More specifically,  FIG. 10  is a flowchart that describes a call service providing method in a network environment including a number of entities according to an embodiment of the present disclosure. 
     With reference to  FIG. 10 , the control circuit  510  of the electronic device  410  is capable of performing the registration of contacts stored in the electronic device  410  of the user in the server  420 - 1  before making a second or third call described above. The registration of contacts is performed to facilitate the call services in a speech-text conversion mode or text-speech conversion mode. When the contacts of individual users are registered in the server  420 - 1 , the users whose contacts have registered in the server  420 - 1  may make a second or third call between each other, as explained above, according to users&#39; requests. 
     The control circuit  510  registers contacts of a user in the server  420 - 1  as follows. The control circuit  510  controls the communication module  520  to register contacts of a user in the server  420 - 1  (e.g., first server). After that, the control circuit  510  of the electronic device  410  receives a token from the server  420 - 1 , and transmits the received token to the server  420 - 2  (e.g., second server). The server  420 - 2  (e.g., second server) checks the validity of the received token. 
     The operations between the electronic device  410  and the servers before performing a second call or a third call may also be performed by other parties&#39; devices as well as the user&#39;s device. 
     When the server  420  ascertains that tokens transmitted from the electronic device  410  of the user and devices of other parties are valid, the user and parties are in a state where they can make a call to each other in a text-speech conversion mode or a speech-text conversion mode. 
     When the servers have recognized that individual tokens from the electronic device  410  of the user and devices of other parties are valid, the user may receive an incoming second call from a second party while on a first call with a first party in a voice call mode. When the user and the second party accept to make the second call in a text-speech conversion mode or a speech-text conversion mode, the electronic device  410  of the user creates a group and the group ID in the server  420 - 2  (e.g., second server) and transmits the created group ID to the server  420 - 1  (e.g., first server). In this case, the server  420 - 1  (e.g., first server) transmits the received group ID to the device of the second party. The device of the second party participates in the group of the server  420 - 1  (e.g., second server), using the received group ID. Therefore, the second communication network establishes a channel connecting between the user and the second party, so that the user performs the second call with the second party in a text-speech conversion mode and the second party performs the second call with the user in a speech-text conversion mode. 
     In the embodiment shown in  FIG. 10 , the first server may be an application server (AS) for performing functions of applications installed to the electronic device. The second server may be a Service Capability Server (SCS) for performing the transmission of messages, data, multimedia data, etc. for groups of electronic devices in a service provider network. Although the embodiment is implemented in such a way that the first and second servers are separated from each other, it should be understood that the first and second servers may also be integrated into a single server. 
       FIG. 11  is a flowchart that describes a call service providing method of an electronic device according to another embodiment of the present disclosure. More specifically,  FIG. 11  is a flowchart that describes a service providing method of an electronic device  410  when a user of the electronic device  410  receives a call from another party while on a conference call with a number of parties. 
     The control circuit  510  controls the communication module  520  and the audio module  550  to provide the user with a conference call function with a number of parties in operation  1110 . The conference call is a phone call where the user and a number of parties hear and talk to each other in voice mode. This type of conference call may be connected via a first communication network, e.g., a circuit switching (CS) network. 
     The control circuit  510  then recognizes that a call has been received from another party in operation  1120 . 
     The control circuit  510  notifies the user that a call has been received from another party, and controls the display unit  540  to display a confirmation request asking the user whether he/she will connect to the second call with the other party in a mode that differs from that of the conference call in operation  1130 . The second call may be connected in such a way that the user performs the second call with the other party in the form of text conversation and the other party performs the second call with the user in the form of voice conversation. Therefore, the confirmation request may be a message asking the user whether he/she accepts the second call with the other party in a text-speech conversion mode. For the confirmation message, the control circuit  510  controls the audio module  550  to output an audio message or controls a haptic module to output a vibration signal. 
     The control circuit  510  is capable of simultaneously performing a conference call and a second call according to a user&#39;s second call request in operation  1140 . To this end, the control circuit  510  controls the communication module  520  to request the second call. When the control circuit  510  receives information that the other party has accepted the second call, it controls the communication module  520  to perform the conference call and the second call simultaneously. 
     Since the second call in operation  1140  is performed in a mode similar or identical to that as in operation  640  of  FIG. 6 , its detailed description is omitted hereinafter. 
     In an embodiment, a call service providing method of an electronic device is implemented to include: receiving a first call from a first external electronic device via at least one communication circuit; during the first call, receiving a request for a second call from a second external electronic device via the at least one communication circuit; receiving the second call based on input via an input device; converting a first voice data from the second external electronic device to a first text data and displaying the first text data on the display; and converting a second text data inputted via the input device to a second voice data and transmitting the second voice data to the second external electronic device 
     In an embodiment, a call service providing method of an electronic device is implemented to include: providing a user of the electronic device with a first call from a first party; receiving a request for a second call from a second party while providing the first call; and controlling a communication module to connect the second call with the second party while maintaining the first call, according to an input from a user of the electronic device, wherein the first call is connected in a first communication mode and the second call is connected in a second communication mode. The process of control a communication module to connect the second call includes: after receiving the request for the second call with the second party during the first call, receiving user input to accept the second call in the second communication mode; and connecting the second call in the second communication mode based on the received user input. The method may be implemented to further include: requesting a third call to a third party according to input by the user; receiving, from the third party, a request to connect the third call in a third communication mode; requesting confirmation from the user to connect the third call in the third communication mode; and when confirmation from the user is received, connecting the third call in the third communication mode, wherein the third communication mode is a hybrid voice and text communication mode wherein a third voice data from the user of the electronic device is converted to a third text data transmitted to the third party, and a fourth text data from the third party is converted to a fourth voice data outputted by the electronic device. The method may be implemented to further include: registering, before connecting the second or third call, contacts of the user in a first server via the communication module; receiving a token from the first server; and transmitting the token to a second server. The method may be implemented to further include: creating a group of contacts when the user accepts the second call, the group of contacts include the first party and the second party; creating a group identification (ID) corresponding to the created group; transmitting the group ID to the second server; and connecting the second call and merge the first call and the second call when the first party and the second party accepts participation in the group. The method may be implemented to further include: receiving a group ID corresponding to a group of contacts created by the third party from the first server when the user accepts the third call; transmitting a request to participate in the group to the second server; and connecting the third call. 
     As described above, various embodiments of the present disclosure are capable of allowing a user of an electronic device to connect calls with a number of parties simultaneously, which include an existing call that the user has with a specified party and a new call that the user receives. Therefore, the user does not need to select one of a number of calls and hold or reject the other calls. Instead, the user may connect to one call in a voice mode and another call in a speech-text conversion mode. In addition, one or more embodiments of the present disclosure are capable of allowing the user to make another call on another topic during a conference call. 
     A programming module according to embodiments of the present disclosure may include one or more of the aforementioned components or may further include other additional components, or some of the aforementioned components may be omitted. Operations executed by a module, a programming module, or other component elements according to various embodiments of the present disclosure may be executed sequentially, in parallel, repeatedly, or in a heuristic manner. Further, some operations may be executed according to another order or may be omitted, or other operations may be added. 
     The above-described embodiments of the present disclosure can be implemented in hardware, firmware or via the execution of software or computer code that can be stored in a recording medium such as a CD ROM, a Digital Versatile Disc (DVD), a magnetic tape, a RAM, a floppy disk, a hard disk, or a magneto-optical disk or computer code downloaded over a network originally stored on a remote recording medium or a non-transitory machine readable medium and to be stored on a local recording medium, so that the methods described herein can be rendered via such software that is stored on the recording medium using a general purpose computer, or a special processor or in programmable or dedicated hardware, such as an ASIC or FPGA. As would be understood in the art, the computer, the processor, microprocessor controller or the programmable hardware include memory components, e.g., RAM, ROM, Flash, etc. that may store or receive software or computer code that when accessed and executed by the computer, processor or hardware implement the processing methods described herein. 
     While the invention has been shown and described with reference to certain embodiments thereof, it will be understood by those skilled in the art that various changes in form and detail may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.