I have an Ipad Air 1, it's running iOS 10. Should I update to iOS 12.4.3? I've heard the battery would be worsened if I updated to iOS 12.4.3. I care a lot about battery life. Should I update? Will the battery truly be worsen? Or is it just a temporary thing and my battery would return to normal after a few hours, days? If I update, I'm afraid I can't downgrade to iOS 10. Also, if there is any way i can update to iOS 11 in 2019, I'd like to hear it, since my goal for updating is just to download some apps I haven't been able to download. Thanks a ton.