There’s been lots of talk about the battery life of the iPhones 4S and 5 after being bumped up to iOS 7 – the iPhone 4S in particular has been whacked by this update.
The iPhone 5 has been fairly untouched, though. There have been many reports of the 4S draining in just hours, and after looking into this problem, we’ve found out how to solve or avoid this drain-pain.
The same thing happened last year after the release of iOS 6, and it seems that it’s nothing to do with hardware – it happened after the installation of updates like iOS 6 or iOS 7 Beta.
It looks like it happens at random, but it’s related to the way in which you install the update.
So, you should back up your phone and make a clean installation of iOS in DFU mode in iTunes. Hold down the sleep/wake button and the home button at the same time.
Then wait until you see the Apple logo, and then keep the home button held down until iPhones tells you you’re in recovery mode.
At this point, you can install a new copy of iOS onto your phone and update to iOS 7 Beta, then restore your data. If you back your old OS up in iTunes, you can revert back to it if you need to.
The battery drain problem in the iPhone 4S is a massive headache, but you should be able to avoid it if you do a clean installation. This drain is most likely to happen if you restore your data having NOT done a clean install beforehand.