Apple iPads come with a 1-year manufacturer's warranty already included. An additional year may be purchased as Apple Care, however, Revel Systems does not and will not pay for the additional year of warranty. If clients so desire, they can take their iPads to an Apple Store and purchase extended warranty.
To see what exactly the warranty covers, go to:
Apple iPad Warranty Info: https://www.apple.com/support/products/ipad.html
To see if the iPad is still under warranty:
1) On the iPad, go to Settings > General > About.
2) Scroll down to where it says Serial Number (alphanumeric, e.g. F85LJMWHFP84).
3) Enter the Serial Number in the following link: https://selfsolve.apple.com/agreementWarrantyDynamic.do
4) Click Continue. It will display the valid purchase date, and whether or not it is under warranty.
To get an iPad replaced:
The client should check to see if the iPad is under warranty using the steps above. If so, he/she should go to an Apple Store and have it replaced at the store.
Note that Revel is always buying iPads to disburse to clients, so most warranties still have a significant amount of time on them. It's usually worth checking if it is still under warranty.