So I just got an iPhone 3GS and of course, I jailbroke it and unlocked it. Since then, the battery seems to be draining really fast. I would put it on standby with 90 % battery and after 4 hours and it's already down to 10%. With this kind of battery drain, I'm not able to use to phone properly and I am quite disappointed in it. This happens with Wifi off, 3G off, SSH off (usually it sometimes turns on by itself), and no Push. I was thinking it may have something to do with the network because my phone had no service for 3 hours and the battery did not go down at all. - Could the battery drain be caused by ultrasn0w? If you guys have any other suggestions to reduce battery drain, please tell me! thanks. EDIT: Solution http://blog.iphone-dev.org/post/144907200/ultratips Unusual battery depletion is almost always caused by people choosing to “Restore from backup” instead of “Setup as new iPhone” when iTunes asks you. This isn’t caused by either the jailbreak or the unlock, but it’s a common 3.0 snafu. The fix is to just re-run the official 3.0 restore and choose “Setup as new” this time. Your music and apps and all that will still be synced, but you’ll get rid of any conflicting wifi, bluetooth, or carrier settings. Then just re-run redsn0w and install ultrasn0w.