Post by Rick on Dec 5, 2016 16:11:07 GMT -6
I've been chasing this one down for the last several months now and have come to the general consensus of "You Don't."
That being said, Apple does allow for downgrades provided that you have made backups to iCloud or iTunes before upgrading. I don't trust the "Cloud," so I haven't used this one. That leaves iTunes. As I have found out the hard way, my backup that I had stored away was incomplete because of how iTunes spreads backup files over several subdirectories within your computer instead of putting them all into one central location. As a result, I've only got the backups to all my apps I had at the time before doing the iOS upgrade to my iPad2. I have nothing backed up as far as the iOS version I had on it at the time. A hard drive failure on my computer sealed the fate of me going back to retrieve the extra files I needed to go any further. So now I'm stuck on iOS version 9.3.5 that sucks big time as far as performance goes.
The extra files I need to restore my iOS to an older version are available at ipsw.me/
The procedure is pretty straight forward as indicated in this one of many guides I have found on the internet on how to do it: www.igeeksblog.com/how-to-downgrade-from-ios-9-to-ios-8-4-1/
The only problem is Apple has a hard line policy of iOS signing. Usually, an older version of iOS loses it signing rights within days of a newer iOS version being released. You can consider yourself lucky if you can find an older iOS version that is still signed that you may want to use. I'm sure there is probably a work-around for developers for testing apps on older iOS versions, but it's certainly not available to the general public.
Another option I've been looking into is OTA (Over The Air) downgrading.
Apparently, a few older signed versions of iOS are still available for compatibility reasons to allow for upgradability to certain iDevices. A few of the more promising tools to use to do this are OdysseusOTA, OdysseusOTA2 from tihmstar.
The only problem in using using this or other procedures I have found on the web is that you need to be able to Jail-Break your device. The iPhone Wiki has a very comprehensive list of what iOS versions and devices that can be jail broken. As it stands right now, anything on iOS 9.3.5 or newer cannot be jail broken. According to the chart, my iPad 2 sits at being jail breakable if it was still on iOS version 9.0.2 or older. So, I'm kinda stuck right now.