You can know exactly when a used car was registered before you buy it, or simply satisfy your curiosity. The database has all the plate numbers from 1971 to July 2012, so you won't have any trouble finding the one you want.
Besides, the application doesn't need to be connected to the Internet, so you can use it anywhere and anytime, even without a data plan.
Fecha Matrículas España is a simple application that has a very specific use. It works great, and its interface is also really simple.