# Usability Testing of Mobile Applications:
## 6 Discussion  
Laboratory research is still more common than field research because the effort involved in organizing, preparing, testing, and analyzing participant samples is considerably less. In addition, a number of well-known usability measurement tools, such as the Software Usability Scale (SUS) or Software Usability Measurement Inventory (SUMI), can be easily adapted for English-speaking users, as well as translated into other languages and used to evaluate mobile usability [136; 137]. This type of research, compared to the presented methodology, requires less time and money, but it provides only a general view of users regarding the pre-assigned aspects of the quality of mobile applications. The advantages derived from mobile usability field studies are either authentic in nature, related to real conditions and settings, or reliable in nature, related to unmoderated design. According to [PERSON] and [PERSON] [138], the need for participants to multitask during field testing significantly increases the error rate associated with task completion and thus the likelihood of identifying specific usability problems. On top of that, some user behavior can only be observed in the field [139], which captures the complexity and richness of the real world in which the interaction between a user and a mobile application is located [140]. In a broader sense, the value of field settings has also been recognized and confirmed by other studies related to the usability of mobile applications [141; 142]. In the field of information systems research, the usefulness of questionnaires has long been recognized [143; 144], and they have been widely used to study mobile usability. The use of a questionnaire as a research method is flexible and cost- and time-effective [145]. It allows for large-scale data collection distributed across a geographically diverse group of participants, as well as the standardization of data without the need for physical presence. While questionnaires are a popular and widely used research method [146], they have certain limitations. By design, questionnaires are often structured and may not allow participants to elaborate on their answers. In mobile usability testing, this can limit the depth of information gathered, making it difficult to gain a thorough understanding of complex issues [147]. Participant observation, in which a study is conducted through the researcher's direct participation in the usability testing, where the questions and discussions arise from the participant's involvement [148], is a qualitative method of considerable interest to the human-computer interaction community [149]. When considering mobile usability testing, participant observation allows researchers to gather in-depth and detailed information with the ability to explore different contexts by actively participating in the settings [150]. Figure 6: Use case of the GAQM framework for the usability study of version \(A\) and version \(B\) of the Flying Flowers app. This allows a researcher to gain insights that may be difficult to capture through other research methods. Participant observation is feasible for both field and laboratory studies but appears to be more difficult to implement for the former approach. In usability testing, thinking aloud is often used to assess how users interact with software, helping researchers to understand user concerns, preferences, and areas for design improvement [151]. Since participants express their thoughts as they occur, thinking aloud provides real-time data, allowing researchers to capture the immediate cognitive processes involved in performing a task [152], which appears to be particularly useful in A/B (split) testing. According to [PERSON] [153], \"thinking aloud may be the single most valuable usability engineering method\". Currently, the method is widely used in usability testing of mobile applications [154]. As interviews allow information to be put into context, users can provide details about specific problems that have arisen.