An Explorative Usability Studyof Smartphone-Based Indoor Navigation

Abstract: Mobile phone usage is constantly increasing, as a result we are becoming more reliant on services provided for mobile devices. Mobile devices and especially smartphones can be used for a variety of purposes and has especially made location based services (LBS) mainstream, where outdoor usage has been the primary scope of use. However, by leveraging the positioning abilities of the Assisted Global Positioning System (A-GPS) and location-sensing techniques based on e.g. cellular towers and WiFi access points (AP), mobile phones can be used to determine a position in indoor environments. As indoor positioning has evolved, early stage systems designed for indoor navigation have been developed. With positioning accuracy set aside, other areas (e.g. usability and design) of indoor positioning and navigation have been sparsely explored, both regarding user behaviour and adaptation of the provided solutions. This study encompasses an experimental deployment of two smartphone-based indoor navigation systems that were evaluated using two methods: self-guided exploration and end-user evaluation. The subject of indoor navigation were approached from two separate viewpoints - Administrator and End-user - with usability as a common denominator. The results from our study clearly showed that systems designed for smartphone-based indoor navigation, have yet to reach their full potential from both viewpoints. Functionality embedded in the systems proved to be very error sensitive, due to a minimal usability margin concerning end-user abilities to orient and navigate indoors. Administrators have to make a thorough assessment of the intended environment, in order to ensure that the system will operate properly and to minimise the time for deployment. Administrators also have to consider the controllability of the provided system, as dependencies towards the creator of the system infer undesired lack of control. If pre-existing infrastructure is to be utilised, such as a WiFi installation, the prerequisites of indoor positioning needs to be ensured by the administrators of the system. Lastly in this paper, our common recommendations are compiled as six guidelines, which are: 1. Functionality and features for orientation and navigation are error sensitive, 2. Positioning technique should be determined based on the environment, 3. Precise positioning is less crucial than stable positioning, 4. Live-tracing is of great importance in terms of orientational feedback, 5. Dynamic floor plans are fundamental for a dynamic navigational system, and 6. Controllability is valuable, dependance should be kept to a minimum.