The ethics of emulation exist in a gray area. While the emulators themselves are legal to create and distribute—provided they do not include proprietary code like a console's BIOS—the distribution of game files (ISOs or ROMs) remains a point of contention.
: These sites may attempt to steal login credentials or personal information through fake registration forms. 3. How to Safely Set Up PS3 Emulation
The official aPS3e app on Google Play does not require a registration key to function. There is a free version and a "Premium" version, but the premium version is strictly for supporting the developer, "aenu". If a site is asking you to "verify" or enter a key to unlock the app, it is likely a scam or malware.
on how to safely set up a reputable emulator for your specific device?