The bill just came and it says that I ve been using gprs(3g or 2g) but every single box in wireless and networks section in settings(mobile networks included) is disabled except wifi.It seems from what I ve read some apps use 3g even if you dont allow it to use it.How do I stop them from using it?Also gps satellites option was disabled but the use wireless networks in location and security was enabled.Does anyone know an app that kills tasks without them restarting?