Apple phones support reloading the system through iTunes or recovery mode. Reinstalling the system can solve some software problems and improve the performance and stability of the system. Users can use iTunes to restore their systems by backing up data and then connecting their phones to their computers. Apple official also provides a recovery mode, users can follow the instructions to enter the recovery mode, and then choose to reinstall the system. Reinstalling the system will erase all the data in the mobile phone, so be sure to back up important data before operation.