PokeMMO, but with some adjustments to the default settings.
First, change the interface style to Android to get the on-screen control overlay. Change the scaling of both sets of buttons to be at least 1.5x to work well on portrait too. I also swapped the A and B button for muscle memory.
Change the zoom to be the lowest possible (3) instead of auto to get an expected amount of the world on the screen. With that, you should be good.
