I have been using an iPhone 4 4.0 jail broken and UltraSn0w unlocked phone for several months now. I am on AT&T but travel internationally and use a prepaid when I travel. Unlock was done with jailbreak me.com

Last week I started seeing miserable battery life, like maybe 5 hours on standby from a full charge.

After uninstalling most everything, including the unlock with no change, yesterday is restored to 4.0.1 and then jail broke again but didn't install anything else other than the cydia essential updates. Charged the battery and then let it sit over night. Totally dead this morning


Restored it again to 4.0.1 this morning and fully charged it again. Been now about 6 hours and the battery gauge is still almost fully charged.

Any ideas what could be causing this?

check the autolock settings to see if you have it set to never.
push notification = on will drain a battery a bit but not to the extend you are describing.
It is strange that it is draining that much even after a fresh restore.

Turns out I spoke too soon. Battery life un-jail broken today was just as bad. Something is wrong with the phone I think.


Bummer. Now I will get a replacement phone that can't (yet) be jail broken

Very strange. After a few days of miserable batt life, restores, a trip to the store (no appointments) and a whole bunch of "try this" from people the phone went back to normal. Jailbroken again with jailbreakme.com and no battery life issues.

Never did figure out what this was but at least I get to keep the phone at has all of the shsh files backed up!

When I did my first JB my battery sucked bad until the very first full charge. Then for some reason it calmed down.

I didn't see that, but this was the case of an iphone4 working for a couple of months now jailbroken and unlocked and then it started its extreme battery usage.

Then it went away and I've had no issues since.

Could be that the battery is faulty. Try to power cycle by turning the phone off, taking out the battery for a few minutes and then turning it on again. You might also want to try draining the battery on standby and then charge it to full before turning it on again. Batteries would usually become erratic after a few months if you don't drain them every now and then specially if there's heavy usage.

After a bunch of tries of all kinds of things after I started this thread, the problem went away. I did lots of stuff including removing almost all apps, all of the ones from Cydia, and all the way to a full restore of 4.01 to the phone and didn't jailbreak. Even that didn't help. Then the problem stopped just as fast as it started.


Now it's at it again. Battery life is going down from a full charge to fully dead in about 5 hours, even if I'm not using the phone at all. I'm at a loss to understand what happened.

Then today, I was switching over my wireless network router configurations to a new one and noticed that even when the phone is "asleep" that the WiFi connection appears to be up and running. My other iPhones (two 3GS both at 4.0.1) and my iPhone 2G (3.1.2) appear to go away from the router's active connections when they go to sleep but the iphone 4 remains in the list of active connections.

Of course, that would explain the battery life. I'm gonna turn off the WiFi on the phone for a while and see what happens.


Any thoughts or suggestions?

iPhone 4/32G, iOS 4.0.1, modem 01.59.00, jailbroken with PwnageTool (MAC) and unlocked using UltraSn0w. (right now I'm on ATT but I do use the phone internationally with prepaid SIMS so that's why I'm running the unlock)

Turning off WiFi didn't seem to change things. Just over an hour since the last post, down about 11% on the battery and the phone has just been sitting there doing nothing


I wonder if there is something constantly looking on the net and keeping the connection alive and is now just using the 3G? Is there a tool that I can install on a jailbroken device that shows what is going on with the internet connection?


time to turn off EDGE and 3G to see what happens now.

Originally Posted by unclemiltie

Turning off WiFi didn't seem to change things. Just over an hour since the last post, down about 11% on the battery and the phone has just been sitting there doing nothing


I wonder if there is something constantly looking on the net and keeping the connection alive and is now just using the 3G? Is there a tool that I can install on a jailbroken device that shows what is going on with the internet connection?


time to turn off EDGE and 3G to see what happens now.

What jailbreak did you use? Did you let the phone activate normally with AT&T before you jailbroke?