Answer to: Touchscreen becomes erratic after a whileNot sure if this applies to iPhones, but iPad screens (digitizers) are fully insulated against random electrical contact while some of the 3rd party screens are not. You can tell if you flip the digitizer over and see exposed metal contacts (copper) anywhere along the base leading away from the "Home" button. Some simple insulating tape or non-conductive material needs to cover these exposed points or random screen problems can crop up. Here's one video discussing this type of problem with iPad mini replacement screens: https://www.youtube.com/watch?v=1_hGBxOP... I don't know if the iFixit screens are properly insulated or not.