I'm going to try out Phoenix on my Amazon HD tablet and Moto phone.
Edited: I had to use MAME PC version to make the phoenix.cfg with the screen rotate laying to the left side. The MAME4droid 2024 Portrait mode enabled wouldn't work for some reason.
No issue on the PS4 controller set up. Took me some time to go back to the MAME games list screen. Moto Phone doesn't have a back button. Just a swap to the right to go back. Show a white left arrow on the screen.