If your iPad is not performing or operating as expected, try a forced restart - as this will often clear an isolated or post-update software issue:
Force restart iPad (models with Face ID or with Touch ID in the top button)
If your iPad doesn’t have the Home button, do the following:
- Press and quickly release the volume button nearest to the top button.
- Press and quickly release the volume button farthest from the top button.
- Press and hold the top button.
- When the Apple logo appears, release the top button.

Force restart iPad (models with the Home button)
Press and hold the top button and the Home button at the same time. When the Apple logo appears, release both buttons.

It is not unusual for an iPad to become warm when being used - more so when using some types of iPad case. High screen brightness and/or CPU intensive Apps will also create more heat.
The key point is that whilst your iPad may become very warm in normal use, the iPad should not become uncomfortably hot to handle. If your iPad is becoming too hot to hold, you should take your iPad along to the Genius Bar at your local Apple Store - where the technicians can examine and test your iPad for faults.
Genius Bar Reservation and Apple Support Options - Apple