On this app, there are three ways to practice Japanese letters, Kanji that relates to Prefecture name of Japan in particular.

The first way is to practice a single Kanji letter selecting from a Letter list page. 

The second way is to practice a Prefecture name selecting from a Prefecture name list page.

The third way is also to practice a Prefecture name though; you can make sure where each prefecture is located in Japan using a Prefecture name list before practicing a Prefecture name you have chosen on the list.

Lastly, I would like you to feel like having a bit of Kanji letters and a simple map of Japan up your Apple Watch, as the saying goes, "have something up one's sleeve."