Question: When did the iPhone 6s Plus from the developer of MessagePad come out?

full_context: Document 1: HP Prime: The HP Prime is a graphing calculator introduced by Hewlett-Packard in 2013 and currently manufactured by HP Inc. It was designed with features resembling those of smartphones, such as a full-color touchscreen display and the ability to expand functionality by means of downloadable applications. It claims to be the world's smallest and thinnest CAS-enabled calculator currently available.
Document 2: Smartphone: The Ericsson R380 (2000) by Ericsson Mobile Communications. The first device marketed as a ``smartphone '', it was the first Symbian - based phone, with PDA functionality and limited Web browsing on a resistive touchscreen utilizing a stylus. Users could not install their own software on the device, however. The Kyocera 6035 (early 2001), a dual - nature device with a separate Palm OS PDA operating system and CDMA mobile phone firmware. It supported limited Web browsing with the PDA software treating the phone hardware as an attached modem. Handspring's Treo 180 (2002), the first smartphone that fully integrated the Palm OS on a GSM mobile phone having telephony, SMS messaging and Internet access built in to the OS. The 180 model had a thumb - type keyboard and the 180g version had a Graffiti handwriting recognition area, instead.
Document 3: IPhone 7: iPhone 7 and iPhone 7 Plus are smartphones designed, developed, and marketed by Apple Inc. They were announced on September 7, 2016, at the Bill Graham Civic Auditorium in San Francisco by Apple CEO Tim Cook, and were released on September 16, 2016, succeeding the iPhone 6S and iPhone 6S Plus as the flagship devices in the iPhone series. Apple also released the iPhone 7 and 7 Plus in numerous countries worldwide throughout September and October 2016. They were succeeded as flagship devices by the iPhone 8 and iPhone 8 Plus on September 22, 2017 and the upcoming iPhone X on November 3, 2017.
Document 4: IPhone 6: The iPhone 6 and iPhone 6 Plus are smartphones designed and marketed by Apple Inc. The devices are part of the iPhone series and were announced on September 9, 2014, and released on September 19, 2014. The iPhone 6 and iPhone 6 Plus jointly serve as successors to the iPhone 5S and were themselves replaced as flagship devices of the iPhone series by the iPhone 6S and iPhone 6S Plus on September 9, 2015. The iPhone 6 and 6 Plus include larger 4.7 and 5.5 inches (120 and 140 mm) displays, a faster processor, upgraded cameras, improved LTE and Wi - Fi connectivity and support for a near field communications - based mobile payments offering.
Document 5: Macintosh: The Macintosh (pronounced as / ˈmækɪnˌtɒʃ / MAK - in - tosh; branded as Mac since 1998) is a family of personal computers designed, manufactured, and sold by Apple Inc. since January 1984. The original Macintosh was the company's first mass - market personal computer that featured a graphical user interface, built - in screen and mouse. Apple sold the Macintosh alongside its popular Apple II family of computers for almost ten years before they were discontinued in 1993.
Document 6: IPod: Apple did not develop the iPod software entirely in-house, instead using PortalPlayer's reference platform based on two ARM cores. The platform had rudimentary software running on a commercial microkernel embedded operating system. PortalPlayer had previously been working on an IBM-branded MP3 player with Bluetooth headphones. Apple contracted another company, Pixo, to help design and implement the user interface under the direct supervision of Steve Jobs. As development progressed, Apple continued to refine the software's look and feel. Starting with the iPod Mini, the Chicago font was replaced with Espy Sans. Later iPods switched fonts again to Podium Sans—a font similar to Apple's corporate font, Myriad. iPods with color displays then adopted some Mac OS X themes like Aqua progress bars, and brushed metal meant to evoke a combination lock. In 2007, Apple modified the iPod interface again with the introduction of the sixth-generation iPod Classic and third-generation iPod Nano by changing the font to Helvetica and, in most cases, splitting the screen in half by displaying the menus on the left and album artwork, photos, or videos on the right (whichever was appropriate for the selected item).
Document 7: IPhone 6S: The iPhone 6S and iPhone 6S Plus (stylized and marketed as iPhone 6s and iPhone 6s Plus) are smartphones designed, developed and marketed by Apple Inc. They were announced on September 9, 2015, at the Bill Graham Civic Auditorium in San Francisco by Apple CEO Tim Cook, with pre-orders beginning September 12 and official release on September 25, 2015. The iPhone 6S and 6S Plus were succeeded by the iPhone 7 and iPhone 7 Plus in September 2016.
Document 8: IPhone 6: The iPhone 6 and iPhone 6 Plus are smartphones designed and marketed by Apple Inc. The devices are part of the iPhone series and were announced on September 9, 2014, and released on September 19, 2014. The iPhone 6 and iPhone 6 Plus jointly serve as successors to the iPhone 5S and were themselves replaced as flagship devices of the iPhone series by the iPhone 6S and iPhone 6S Plus on September 9, 2015.
Document 9: IPhone 7: iPhone 7 and iPhone 7 Plus are smartphones designed, developed, and marketed by Apple Inc. They were announced on September 7, 2016, at the Bill Graham Civic Auditorium in San Francisco by Apple CEO Tim Cook, and were released on September 16, 2016, succeeding the iPhone 6S and iPhone 6S Plus as the flagship devices in the iPhone series. Apple also released the iPhone 7 and 7 Plus in numerous countries worldwide throughout September and October 2016. They will be succeeded as flagship devices by the iPhone 8 and iPhone 8 Plus on September 22, 2017 and the iPhone X on November 3, 2017.
Document 10: IPhone 6S: iPhone 6S and iPhone 6S Plus (stylized and marketed as iPhone 6s and iPhone 6s Plus) are smartphones designed, developed and marketed by Apple Inc. They were announced on September 9, 2015, at the Bill Graham Civic Auditorium in San Francisco by Apple CEO Tim Cook, with pre-orders beginning September 12 and official release on September 25, 2015. The iPhone 6S and 6S Plus were succeeded by the iPhone 7 and iPhone 7 Plus in September 2016.
Document 11: MessagePad: The MessagePad is the first series of personal digital assistant devices developed by Apple Computer for the Newton platform in 1993. Some electronic engineering and the manufacture of Apple's MessagePad devices was undertaken in Japan by the Sharp Corporation. The devices were based on the ARM 610 RISC processor and all featured handwriting recognition software and were developed and marketed by Apple. The devices ran the Newton OS.
Document 12: Macintosh: As for Mac OS, System 7 was a 32-bit rewrite from Pascal to C++ that introduced virtual memory and improved the handling of color graphics, as well as memory addressing, networking, and co-operative multitasking. Also during this time, the Macintosh began to shed the "Snow White" design language, along with the expensive consulting fees they were paying to Frogdesign. Apple instead brought the design work in-house by establishing the Apple Industrial Design Group, becoming responsible for crafting a new look for all Apple products.
Document 13: IPhone 7: iPhone 7 and iPhone 7 Plus are smartphones designed, developed, and marketed by Apple Inc. They were announced on September 7, 2016, at the Bill Graham Civic Auditorium in San Francisco by Apple CEO Tim Cook, and were released on September 16, 2016, succeeding the iPhone 6S and iPhone 6S Plus as the flagship devices in the iPhone series. Apple also released the iPhone 7 and 7 Plus in numerous countries worldwide throughout September and October 2016. They were succeeded as flagship devices by the iPhone 8 and iPhone 8 Plus on September 22, 2017, and the iPhone X on November 3, 2017.
Document 14: IPad: In October 2014, Apple released the iPad Air 2 and the iPad Mini 3. The iPad Air 2 is the first iOS device to feature a triple core CPU and 2GB of RAM. As well as being thinner and faster than its predecessor, the iPad Air, it features Touch ID and is available with a gold color option. The iPad Mini 3 is similar than the iPad Mini 2 in design and hardware, but also includes Touch ID and available in gold color.
Document 15: IPod: Though the iPod was released in 2001, its price and Mac-only compatibility caused sales to be relatively slow until 2004. The iPod line came from Apple's "digital hub" category, when the company began creating software for the growing market of personal digital devices. Digital cameras, camcorders and organizers had well-established mainstream markets, but the company found existing digital music players "big and clunky or small and useless" with user interfaces that were "unbelievably awful," so Apple decided to develop its own. As ordered by CEO Steve Jobs, Apple's hardware engineering chief Jon Rubinstein assembled a team of engineers to design the iPod line, including hardware engineers Tony Fadell and Michael Dhuey, and design engineer Sir Jonathan Ive. Rubinstein had already discovered the Toshiba disk drive when meeting with an Apple supplier in Japan, and purchased the rights to it for Apple, and had also already worked out how the screen, battery, and other key elements would work. The aesthetic was inspired by the 1958 Braun T3 transistor radio designed by Dieter Rams, while the wheel based user interface was prompted by Bang & Olufsen's BeoCom 6000 telephone. The product ("the Walkman of the twenty-first century" ) was developed in less than one year and unveiled on October 23, 2001. Jobs announced it as a Mac-compatible product with a 5 GB hard drive that put "1,000 songs in your pocket."
ground_truth: September 25, 2015
sub_queries: MessagePad >> developer Answer: Apple
when did the Apple iphone 6s plus come out Answer: September 25, 2015