Front Glass
This repair replaces the front glass, it can also help with touch screen problems

LCD Display
This will repair the display, the part that display the imagery.

Charging Port
If the device isn’t charging this repair will most likely solve the problem

Wi-Fi Antenna
This repair will assist if the device is having Wi-Fi problems

Power/Volume/Mute button
This repair will replace the cable that controls the lock/power button as well as the volume buttons and mute switch

This will replace the battery. To replace the battery a screen replacement is usually required as well.