If you want to play with Gamepad, than i would suggest an DosBox and/or ePSXe installation and then Games like Wing Commander, TIE-Fighter or Colony Wars
And is your device fast enough, maybe it is also ready to run a PS2 Emulator for the PS2 Port of Freespace 2
Even i dropped all further development of the ports on the penultimate generation of consoles with the end of 2017, because they were not used anymore and so to have more time for other things.
Well, i have to say, that i am not playing with Gamepad on Smartphones, because i am only playing if i am on the way or have to wait a few minutes for a friend.