Phone screen protectors are thin sheets of transparent material that are applied to the screens of smartphones and other mobile devices to protect them from scratches, smudges, and other damage. Screen protectors are commonly made from tempered glass or plastic. 

Tempered glass protectors provide better scratch resistance and feel more like the original screen. Screen protectors help to prevent scratches, cracks, and other damage to the phone's screen. They can also reduce glare and fingerprints.  

Proper application involves cleaning the screen thoroughly to remove any dust or debris, aligning the protector with the screen, and then carefully pressing out any air bubbles. There are different types of screen protectors available, including clear, matte, and privacy screen protectors.

 Clear protectors offer basic protection without altering the appearance of the screen, while matte protectors reduce glare and fingerprints.  Screen protectors may need to be replaced periodically, especially if they become scratched or damaged. screen protectors are an inexpensive and effective way to protect your phone's screen from damage and extend its lifespan.