Q: My sons iPod touch login screen is too large causing incorrect password entry. How do I restore the screen to normal size?

Hi, I am having a problem with an iPod touch. My son has enlarged the screen and when he tries to enter his pin it is incorrect. Can anyone describe how to reduce the screen to allow entry of the security pin?

Failing that is it a complete reset?

The pc I normally sync with has died so I cannot plugin to that pc.

Thank you for reading and any suggestions.