A tweak which will helps you to extending the battery life on your iPhone4. This tweak will auto turn OFF the 3G radio when you lock yo ur iPhone turn it back ON as soon as you slide to unlock your iPhone.
As apple official spec , this tweak will extending the battery life for 100% (as Up to 7 hours on 3G, up to 14 hours on 2G (GSM) ). You can choose enable auto turn OFF by Screen Lock or Passcode Lock.
iPhone 4 ( 4.3.3, 5.1.1 ),
iPhone 4s (5.1.1)
Note: Support GSM device, do no support CDMA device ( Verizon, Sprint , China Telecom ).