How to stop unnecessary usage of 3G and GPRS Data by 8

8 is made for those who mostly work on
Wi-Fi or use time limited data packs, especially 3G. But those who use space limited data packs (e.g. 2gb @ x
money), it becomes difficult for them to work on 8 pcefully because
8 uses a big part of it in background and also in foreground and very
little is left for us to use. It becomes a total wastage of money to surf
internet