There are some similarities, but T9 only uses 8 keys for letters, 3-4 letters per key, and the letter assignment to keys is based on alphabetical order. I'm using 9 keys for letters, with the letters distributed based on letter frequency. Ideally common letter combinations would be on adjacent keys.

Thanks for the response.

How did you create the keyboard?

By modifying an existing keyboard from Github.

I take it that keyboards are compiled into the program, not interpreted by it. I'll merge mine and see how that goes.