如何向用户展示如何在android中写一封信？

I am working on a language Learning android app. I want to include a feature on how to write a particular letter of a particular language. So, the general idea is when a user clicked on a letter say 'A',a pop up activity appears and A is written with a pencil, i.e., sort of showing the user how to write A.I am working on a language Learning android app