@FAST6191 : so basically
this forum section
As far as I'm concerned, the discussion may be moved there, but here's my stance on the (admittedly pretty broad) topic: there's some quality stuff on there.
* the "...oid" emulators are pretty popular. My guess is that it's because they were first, because I can hardly find them on the google play store.
* retroarch is the main "go to" emulator for everything. The main disadvantage is, well...that it has everything. I tried using it, but I always end up lost in the options.
* an alternative to this is matsuplayer. It doesn't emulate as much systems, but plenty good and decent ones. It required me manually binding buttons for each system(1), but this had to be done just one single time. PSX, snes, NES, N64 and probably GBA works fine (have only tested the latter for about 10 minutes, so don't hold me on to the last one). In fact, to my embarrassment I found it even better at N64 emulation than the paid version I got a few weeks before.
It furthermore does some other systems like PSP and NDS, but I haven't tested those (I
think it's slightly worse at NDS than drastic, but I haven't done much comparisons). It's free, meaning that it shows some ads, but never during games.
* PPSSPP is imho the perfect PSP emulator. Not only does it emulate a great system, but the UI works intuitive, simple, clear and with all bells and whistles you (probably) might want.
* unless I'm seriously mistaken, drastic is still the best D/s emulator on android.
* on dolphin (gamecube/wii)...there's a recent discussion on here. In UI terms, it's certainly a good one, but I haven't properly tested it for the obvious reason that my gaming device isn't strong enough.
(1): I use a gpd xd+