Q.:	What is this site about ?
A.:	For more than fifteen years, you are able to connect your computer with your GSM/UMTS mobile phone. Initially, this allowed to send FAX and surf the Internet wirelessly. AT commands known from land-line modems are used. Soon, you were enabled to edit phone numbers and manage your short messages (SMS). Later, each manufacturer extended this set of commands for example for calendaring. Instead of creating more and more AT commands, some manufacturers introduced their own binary protocols which are started by an AT command. Infrared (IrDA) introduced a binary protocol to exchange objects (OBEX). OBEX got adopted for Bluetooth and AT commands. Additionally, other protocols used OBEX to exchange their messages to explore the file system, synchronize data stores, and manages SMS in a more specialised way than AT commands do. The following pages shall be a starting point, a tutorial with a trail, collecting technologies and their (sometimes very different) implementations. Historically, there is no single technology covering everything, yet. Each tab presents a step on this trail. The tab currently visible is highlighted. Later, steps (like OBEX) include additional tabs at the bottom for more details. Let us start with the first tab …
Q.:	I am not into computers but design a car-kit. Which protocol should I use ?
A.:	In this case, start at the end of this tutorial and go the trail backwards.