A quick fix for iOS 5 battery issues
Apple today acknowledged that the reports of poor battery life in iOS 5 are indeed bugs in the operating system’s upgrade to iOS 5.
I experienced these issues myself last weekend after updating from version 4 to 5. My battery was only lasting a couple hours but I think I figured out (as many others have by now) that the issue came from signing up with iCloud.
If you’ve noticed your phone getting fairly warm, and your battery draining far faster than before, the first place to look is your contacts. Check to see if you can go back to view “All Contacts” and if there are multiple different accounts being synced.
The problem isn’t simply having multiple accounts for your contacts, as I’ve tested it with completely separate accounts and do not experience any issues. The problem seems to be caused by “Linked Cards”.
If you look through your “All Contacts,” look to see if there are any Linked Cards (like in the picture to the right). These Linked Cards seem to be causing the battery drain issue. I did a quick packet capture on my network and found that when I had contacts that were linked, my phone was constantly sending and receiving data.
Luckily, for security sake, this data was encrypted so I can’t say exactly what is going on, but it appears that when there are Linked Cards, your iOS device is constantly sending out updates to the contact, your contact is then seeing the new update on your other account, sending data back, and creating a loop.
On WiFi this won’t be a huge issue, but when you are on 3G, it will eat through your battery quickly.
The simple fix, until Apple solves this with an update, is to go into Settings -> Mail, Contacts, and Calendars -> and turn off all of your Contacts. Make sure when you do this that you select the option that says “Delete from My iPhone” or your iPhone will create a local copy of all your contacts on your phone, which recreates the issue.
After that, only turn back on one account for your contacts, or more if you’re sure there aren’t any duplicates between the accounts. Go back into Contacts and check to see if there are any Linked Cards.
Once you’ve done that, you should notice your battery life return to approximately what it was before updating to iOS 5. Traffic coming to and from my phone was greatly reduced after I did this.
Your mileage may vary on this as it appears other people are also having issues with Location Services eating up more battery than usual as well.
Hope this helps!