Bluetooth and GSM I am not sure that changing SIM cards will help. GSM Cell phones have an electronic serial number (independent of the SIM card, it's in the phone itself) and it might be possible to track that number when the phone is used. Anyone know whether that serial number is transmitted over the network? If you have friends that you trust that have technical knowledge about cell phones ask them for advice on how to stay anonymous. Please do not underestimate the vulnerability of things like Cell Networks, Wireless Access points (WIFI) to listening and tracking location. Sometimes it might be unavoidable to use Cell or WIFI. Try to "spread" your activity over many locations if possible. Try to avoid sending pictures/videos/twitters/emails from the same location over and over again. If you're sending with a laptop or phone using WIFI hotspots at places like internet cafes and bookstores with free internet access try to alternate these loactions and spread them across a large area; it might prevent you from being tracked, and if you are already being tracked it might throw them off. Consider having multiple phones with their own phone numbers if possible. Bluetooth phones can also be tracked when the bluetooth is enabled. Every bluetooth device has a unique hardware address which can be monitored, although bluetooth range is only a few meters. Many phones let you enable and disable bluetooth capability; most often it is found in the phones "preferences" or "settings", etc. menu. If you have Bluetooth on your phone and never use it and you do not ever plan to use it then disable it, it it will save battery life too. Be especially careful if you connect to the internet using WIFI (wireless routers at home, coffee shops, internet cafes). I have first hand experience cracking WIFI access points and I can tell you that it is very easy to monitor internet traffic over WIFI using free software. See http://www.aircrack-ng.org Try to connect to the internet with a "wired" connection whenever possible, including when you are home. Even encrypted WIFI connections can be monitored with ease from the office/house/apartment/store next door. Wired internet connections are an inconvenience but it is important to know that it is very easy to intercept information passing over WIFI, especially in urban environments where it is easy to observe without being observed. Prefer "wired" over "wireless", it removes one layer of exposure. Consider using Bluetooth to upload to a computer or another phone if your phone is unable to upload and then upload from that other phone or computer. This can be usefull if you have information on the phone but cannot send it by the Cell network for some reason. Seek out friends with technical knowledge, they can figure out the process on your particular phone and show you how to do it. You can enable bluetooth, send, and then disable it if you are going to a public place and suspect that they are "snooping"