I installed the first iOS 9 beta last week and had been using it on my iPhone 6 Plus until last night. I liked some of the new functions, like the recommendations for contacts and other features offered in the new software, but needed to get back to iOS 8.3 as soon as possible.
I’m not developing for the platform, and I use the iPhone 6 Plus as one of my two primary daily drivers. iOS 9 isn’t ready for that sort of use yet — it’s not meant to be, I just wanted to try it for a bit — mainly because the battery life is nothing short of atrocious. So, yesterday, I downloaded the official iOS 8.3 build and reverted back.
If you find yourself in the same spot, here’s a quick and easy guide to reverting yourself.
1. Take note: Apple warns that you can’t restore to an earlier version of iOS, but you can. First head to Apple’s developer site (you’ll need the $99 annual account to access the software) and download the appropriate version of iOS 8.3 for your device. It’s about 2.2GB big, so it’ll take some time depending on your Internet conneciton.
2. Attach your iPhone to your computer using a USB cable and open up iTunes.
3. On your iPhone, go to Settings > iCloud > Find my iPhone and toggle it to “off.”
4. Open your iPhone page and, while holding the Option button on your keyboard (or Shift key on a PC) tap “restore.”
5. Select the IPSW file you downloaded earlier from Apple’s site.
6. Sit back and let your phone do its thing. Once it reboots, you’ll have the option to log in and restore an earlier backup of your last iOS 8.3 build.
That’s it. It takes a while, but if you’ve backed up your phone and use Apple Photos, everything should remain intact. It’s not that big of a headache, just takes a little while.