Musical note symbols on Android

Question

I'm working on a piano quiz app, and I've reached the stage where I need to write every letter note on the keyboard. More specifically, the musical letter will display on the key when the user presses a key while trying to determine what note was played.

This is a picture of the app when a key is pressed by the user:

My question is related to the musical symbol flat:

How can I create that symbol and use it in the application? For instance, the musical symbol for flat, dflat, is displayed as "DB," and I need to transcribe it as "Dflat."

Edit: Text views of the letter notes are displayed.