My wife and I both just upgraded our iPhone 6's because they became unusably slow after iOS 11. Prior to the upgrade they had been running fine with no issues. We tried many things including disabling all background app usage, full wipe and restore, etc. My wife eventually took hers into the Apple store and they said they didn't know why it was slowing down but that she shouldn't have upgraded and that there was noth…
The iPhone now goes to the garbage bin adding to pollution even though it can run the OS just fine without being crippled via update.