How to use, learn, and practice Dvorak layout with hardware external keyboards? I have an hardware USB keyboard I want to practice Dvorak using my Android device. I've tried several games and such that purport to be typing games or tutors and they are all horrible, or at least clearly designed for other purposes. (Some of them even disable external keyboards because they have leaderboards for speed).

I'm looking for a gimmick-free typing tutor for Android that teaches Dvorak layouts.

Also, how do I convert qwerty input to dvorak?
I solved this by installing Termux, which is a "terminal emulator".  This particular terminal emulator can install gtypist for you, which is a superb, well thought out free and open source typing tutor, well-known in the linux world.  gtypist is very easy to use, and you only need to know two Termux commands.  Just install Termux from the Play store, open a new session (if not automatically done) and type:

apt install gtypist


and press enter/go/return.  It should download and install, and might ask you to confirm.  After that, use the command:

gtypist


(and enter/go/return) to use the tutor.  Instructions for tutor will be on screen.  Happy typing!

If you have a dvorak keyboard, then great, this should work out of the box provided you android device language settings are correct.  Otherwise I found an app called External Keyboard Helper (Demo/Pro) to be extremely powerful in solving individual key map issues, as well as supporting every layout I've heard of.  I tried the demo on one of my devices and once in a while it inserts text "... DEMO VERSION ..." into what I'm doing, but pro version is only $1.99 as of this writing.

These apps also support other layouts, including Colemak, and gtypist is extensible, so you can install other lessons (not tested on Termux version, but I don't see a reason why it wouldn't work).