Don't Install iOS 12.1.1 You're Worried About Problems
If you're having an excellent experience on iOS 11, iOS 12.0, iOS 12.0.1, or iOS 12.1 and you're nervous about wrecking your device's performance, you might want to hold out for a few days.
The iOS 12.1.1 update fixes several annoying iOS 12 problems, but its brought its own set of issues to iPhone, iPad, and iPod touch owners.
The list of iOS 12.1.1 problems includes abnormal battery drain, issues with first and third-party applications, broken Bluetooth, problems with Wi-Fi and cellular data, installation issues, lag, random reboots, issues with Face ID and Touch ID, and problems with 3D Touch.
Other iOS 12.1.1 bugs include an orientation glitch, a Folder in Dock bug, a lock screen time bug, and iCloud Keychain issues.
If you're feeling leery, you might want to wait for the next version of iOS 12 to arrive.