Hi Andy, welcome to AF!

You've posted in the original Galaxy S forum, not the Galaxy S2 forum. If you let me know which version of the S2 you have (the models differ slightly based on the network although most non us variants are the same), I can move to the appropriate section for you. That way users who own the device will be able to assist.

 

We hope so too! Moved to the SGS2 International forum.

What are you using to shut off apps? The inbuilt task manager or something like Advanced Task Killer?

 

Tell us what you have running on your phone. Are you using any software that polls the server on a regular basis. There is usually a reason the battery all of a sudden gets consumed.

Also what kind of coverage do you have. Very poor coverage will ravage your battery

 

Have you tried it without Juice Defender? I actually found Juice Defender to have the opposite effect of what it was supposed to.

Yep, if you have weak/no signal, the phone will push more power to the radio in an effort to get a better one. That might be what the issue is (I'm 99.99% sure it is).

Re the updates, is your brothers handset branded with network software or unbranded?

 

fully charge the battery, switch off the phone, remove the battery for about 30 seconds,then reinsert the battery and switch on. This gives the charge meter to recalibrate itself. good luck