Mike Fikes | Morse code CW straight key connected to phone via BLE @MikeFikes | Uploaded January 2023 | Updated October 2024, 3 hours ago.
The app is Morse Mania. The device is an Android phone; I haven't sorted the same for iPhone.

I suspect it is too slow to use this way unless further optimized in some way.

A subsequent demo with paddles youtu.be/O0wdYhWQfyg