Identify drawing in character - Canvas (Android)

Question

I can already draw on the screen using a DrawingView, as shown in the example:

I wonder if there is any library to identify the drawing and check if it is a character, and if possible, give a percentage of similarity.

Basically, what I want is:

Draw a

To

identify that letter in the code, and say how much % of the letter’s resemblance is.

Do you know of a library that does something similar? If you have done something similar, can you give me a light? I googled a lot, but I didn’t get to something that guided me...