Using Emacs on Android, for me, means using Termux and installing the available emacs package. I knew that there would be lots of muscle memory to overcome, so I just started using Emacs for random things, like simple checklists. This gave me the chance to catch myself trying to treat a phone (primarily touch-oriented) like a laptop (totally keyboard-driven).
Surprisingly, it took me quite a while to figure some things out. For example, Termux comes with a row of special keys above the regular keyboard. For several days, I was still using the arrow keys in that row to position point.
Duh. For all practical purposes, I could just touch the text and place point instantly. Didn't get that right away. Finally realized that I could just tap the text near where I wanted the cursor to be, and then use either the arrow keys (or the built in Emacs cursor motion keys, e.g., C-f) to put the cursor in the right spot.
I must have been leaning on C-v a half-dozen times before it hit me that I could just touch-scroll the text. On the other hand, selecting text is faster and more reliable with C-x SPC & repeated C-n commands.