You don't use apps like "SnoopSnitch"

First of all, there is nothing wrong with apps like "SnoopSnitch" in general. We can be glad that there are people who deal with this matter and build such apps. Nevertheless, you have to understand that such apps are completely ineffective in the vast majority of cases. SnoopSnitch, for example, only works on 2G and 3G networks if your phone is rooted and if a very special chip is installed on the mainboard of your device. You need to understand that communication with the mobile network is a completely opaque black box for your operating system. Your operating system and your apps are not able to control or monitor communication with a radio tower (base station) in detail. This means that the wireless network can communicate with the chip on your device without it being aware of it. This is due to proprietary, commercial hardware that is not open source. This is also why you can be roughly located by silent SMS (stealth ping). The radio chip in your phone registers this, but does not report it to your operating system. Only a few chips have interfaces that allow the operating system to monitor them. SnoopSnitch only exists for this purpose. The only sensible defense is an anonymous SIM card.