So my iphone 6 stuttered alot in ios11 to the point it was too unberable, so i decided to revert back to 10.3.3. Now the problem i have is when i run any application, it'll just freeze and stay at the app's loading screen for like 1 minute untill the "loading wheel" shows up and i have to unlock the phone again. I tried upadting apps, deleting and installing them again and nothing works. Not even the phone app - it just crashes untill it reboots itself, or if i'm lucky, goes back to main screen sometimes. Anybody knows what to do?