Abstract
Smartphones are among the most popular communication devices there are today. They have the functionality, the flexibility, the prevalence and the economic and technological growth that makes them interesting for new applications. This thesis will focus on the use of smartphones as communication terminals without the use of mobile cellular networks. It explains how smartphones can be used for communication in situations when the mobile network is out of range or not working. These situations include emergency situations in case of hurricanes or flooding, but also less demanding situations where alternative communication may be useful. This thesis compares the current communication technologies available on smartphones and explores the alternatives in order to improve the use smartphones in communication without mobile networks. Finally, the thesis proposes an implementation where a radio module is used together with an Android smartphone to create a wireless messaging system.