The process for repairing a broken iPad screen varies between models, but most screens, including iPad 4 screens, must first be heated to melt the adhesive that holds them in place. Owners can then use a small plastic tool to reach beneath the mute button and pry the screen upward.
Thermal heaters can melt the adhesive fairly quickly, but it's important to keep from heating other parts of the iPad too much. Hair dryers work as well but can take far longer. Some companies offer tools designed to heat the screen; they're generally heated in a microwave and laid on the edge of the screen while it's being removed.
There are a number of tools designed to help pry screens off of tablets, but plastic guitar picks are popular as well. While prying the screen off, owners might want to use plastic to keep other parts of the screen propped up to prevent them from adhering again.
If the display needs to be removed as well, owners can access it by unplugging its connection to the processor and battery and removing screws. The new glass screen can be placed with glue designed for screens, but it's often easier to use adhesion tape designed for screens. This tape generally comes with repair kits sold online.