## 2 Literature Review  
Smartwatches have received significant attention for their versatility, which satisfies a wide range of consumer interests, including fitness and health monitoring [4]. Other than basic health and fitness features, smartwatches offer a wide range of features varying from person to person, such as real-time vital signs and overall health monitoring in senior people with Parkinson's, heart disease, or other chronic conditions. In addition, they may capture both crucial and trivial data regarding patient location and behavior more quickly and precisely [16]. According to recent IDC surveys on wristwatch usage, the industry will continue to expand exponentially, with 373 million units expected to be shipped in 2020, up from 100 million in 2016. In 2016, smartwatches made up 25% of all smart wearables. Although smartwatches have a wide range of functionalities, they still face technical and usability challenges, such as aged people being less familiar with new technologies or ease of use or comfort issues for patients [17]. The usability testing needs to examine how consumers really use their smartwatches rather than observing how they were intended to be used. The usability test aims to understand consumers' requirements of these devices through the examination of usability concerns connected to the real tasks that users undertake using their smartwatches [12]. Despite many studies exploring the usability, perceived value, and role of smartwatches in patient monitoring, only limited research has evaluated the relationship of usability and brand factors influencing usability using different usability evaluation methods. This section provides a summary of the fragmented research on wearable technology. [PERSON] et al. [18] proposed a novel method for evaluating a smartwatch's usability based on eye movement tracking. The eye tracker recorded the testers' eye movements, and the eye movement data were added to the system for calculating the usability rating index. In the study, 10 participants were asked to perform specific tasks with Motorola 360 smartwatches and were interviewed afterwards. The results of the task test showed that eye movement data can accurately assess the icons on smartwatch interfaces and illustrate how users search for certain features. [PERSON] et al. [19] completed a study to identify challenges in smartwatch usability using in-depth interviews. Many users appeared to find mobile devices convenient for checking pushed alerts. However, smartwatches obtained a poor response when individuals tried to interact with visually rich material. According to the study, individuals like to use smartwatches to listen to music and check the weather. The study of [PERSON] et al. [20] observed how usability, brand, and price influenced customers' impressions of smartwatches in Indonesia. In order to conduct the study, 116 Indonesian respondents were surveyed. The participants were less concerned with usability and instead focused on brands and pricing when making their purchases. Most of them did not consult evaluations and recommendations from others when they already had a brand in mind. However, one of the shortcomings was the limited number of participants involved, as with a greater number of participants, the results could be generalized to Indonesia's smartwatch users. [PERSON] et al. [21] designed a nurses' watch app with the Motorola 360 smartwatch in order to automate patient monitoring and checklist systems. The usability of the IT systems, including complexity, training, and need for support for the user interface, was evaluated using the system usability scale (SUS). The mean score in the SUS resulted in the average score as the question on comfort and security from the SUS questionnaire received very poor marks.