This book is about the architecture, the protocols and the implementation of a mesh based service on Android devices to provide Internet connectivity in areas which are either not covered by Internet Service Provider (ISP) infrastructure or where it is too expensive to use the ISP infrastructure, e.g. abroad. As a result of this work there is a working Android app which enables Android devices to use the Internet with help of other Android devices in reach. This usage happens in a secure way. It is similar to tethering known in Android 2.3 and upwards but allows for anonymous indirect...