Any good ps3/4 emulators ? Either a ps3 or ps4 ? For an Android ? No. Considering the technical horsepower & architecture of both the PS3 & PS4, it requires a high-end Personal computer for the PS3 (albeit, the developers haven't offered any reasonable figures. Only broad requirements) & a thing that isn't quite available in the public marketplace for specs to emulate the PS4 (although it's a bit too "hot" when it comes to market safety that Sony & ESA would easily pursue C&D's on them).

Android devices, also the high-end gaming-geared devices are not capable to handing the processing requirements...

not to mention the RAM requirements (around 2- 8 GB's) & storage space requirements (some video games acquiring as much at 50+ GB's of space... most phones typically have around 16-32 GB's & microSD cards support of all cell phones max out around 256 GB's) on the execution side of the consoles... significantly less taking care of the controls. At this time, you shouldn't be prepared to emulate anything beyond the beginning of this millennium (around the PS2 / GCN / XBox era) on your phone without major issues.