Android is a fast growing platform with a lot of users and applications on the market. In order to challenge the competition, a new software product should be designed carefully, conforming to the platform constraints and conveying to the user expectations. This research focuses on defining a suitable architecture design for the specific use case of interest, an Android application focused on location based data. The research process is backed up by a prototype application construction with features such as location based reminders and mobile communication with web services. Moreover, an analysis has been conducted on existing products with the proven quality, to extract information on current best practice implementations of several interesting features. Furthermore, the demand for targeting multiple platforms with the same application motivated a research on portability and reuse of code among different platforms. The constructed system is divided into a client-server pair. Opposite to the client (mobile) side, the server side analyzes the process of extending an existing architecture by integrating it with a web service project used for exchanging data with the mobile devices. Finally, the thesis is not strictly constrained to the given use case because it presents several general concepts of application design through architectural and design patterns.