It didn’t take long, did it? No sooner has the latest iOS version been rolled out, users have started complaining for shortened battery life on their iPhones. The latest update for iOS, which bumps the version up to 6.1.3, was rolled out to fix the lock-screen bypass vulnerability issue. According to the details released by Apple, this update was not meant to do any tweaks to the battery usage on the device.
The Apple Support forums are now fairly active with people complaining that the battery on their iPhone is now discharging quicker than before the update.
On one of the threads, someone using the handle Joe says, “It’s draining about 1% every 7 minutes but that’s with the phone not in use. In contrast, last week before the update I would charge my phone at night (and on a day without use) it would still be around 99% when I arrived home from work (roughly 12 hours later). Now my phone is dead before I even get home. This may be an odd issue affecting only a handful of people, but it is clearly real and needs a solution.” Another user using the name peanutbuttachampagne says, “Same story over here. I had around 80% last night when I set my alarm before going to bed. Woke up this morning and my phone was dead. I completely missed my alarm. A fix would be very much appreciated.”
One helpful user, using the forum name Markbob917 has given a step by step guide to what is essentially a trick that works usually. “I can confirm mine is now fine. Go to settings. Mail, contacts, calendars. Go into iCloud and turn all switches to OFF one by one make sure you save all to iPhone though not just delete. Then go to each other mail account and repeat this procedure again making sure you select keep on iPhone not the delete option. Once they’re all turned to off check your calendar to see if everything is missing off it and then you need to do a hard reset by holding the home button and the on/off button until the phone turns itself off. Once it’s come back on go back into settings and mail and turn each switch (or each you want) back to ON. Then make sure all your apps are closed lock the phone and leave it for 30 mins and then check the battery hopefully if like mine it shouldn’t of dropped at all. This worked for me hopefully it will work for others out there”
Unfortunately, some users are reporting that this trick is not working for them. One such user is Timurjonchik who says “I did the same thing twice and i don’t even have an exchange account. It still drains battery and for some reason the gets very hot even when i don’t use it. Once again my phone was pefectly fine untill I made an update”, along with an icon of a sad face. No wonder iPhone users are disappointed.
If you happen to look at these posts in detail, there seems to be no particular version of the iPhone that is facing the issue, with iPhone 4, 4S and iPhone 5 users complaining almost equally loudly. At the moment, Apple has not spoken about a fix, or a iOS 6.1.4 update that will sort out the battery drain issues. In the meantime, we suggest you retry the steps that Markbob917 has listed, and once you have done those, let the iPhone battery drain out completely and the device automatically shuts off. Then, charge it right up to 100% in a single charge cycle, and that should kill all the tasks that may have still been chewing up resources in the background.
Source: Apple Discussions