This guide should be used as a basics guide to emulators. For more in depth instructions on running specific emulators on various Android devices please check out our How To section. Let’s start out with some terminology from the emulator world, but also a little info on the legality of this whole emulator world.
Emulator: An emulator is a software clone of real life hardware. That Nintendo NES that’s collecting dust in storage has been digitally cloned by developers to run on all types of devices. For us, that’s Android devices. Emulators are software programs with interfaces where you can launch games or ROMs in this case. Emulators are seen as legal even by some console makers. No real intellectual property is stolen in their creation so most everyone just accepts them as legit. ROMs, however, are a little grey.
ROM: This is what they call games in the emulation world. ROM stands for Read-Only Memory, which is actually the piece of a cartridge where the game is stored. This memory is dumped into a small file on a computer and is then refered to as a “Rom”. So there is a ROM of Super Mario World and a ROM of Final Fantasy II. Without ROMs an emulator is like a game system without any games. Where the legal grey area starts to come in is with ROMs. Nobody has ever been sued or gotten into any trouble for downloading ROMs, but it’s the widely held belief that owning ROMs of games you personally own is legal. This is all legally untested waters, which is where the grey area comes in.
Bios: Some emulators require a BIOS file to operate or at least operate at maximum efficiency. BIOS is what they call the software that is inside the actual console that runs it. SNES has a BIOS, Playstation has a BIOS, XBOX 360 has a BIOS. Some emulators require a copy of the BIOS for the system you’re trying to emulate, especially more recent advanced emulators like Playstation. BIOS files are another legally grey area. When you own a console you have a license to use the BIOS on that console. There are plenty of tools to allow you to extract the BIOS file from your console for use in an emulator, and that is generally accepted as legal. It however, is also generally seen as illegal to download copies of BIOS files on the net, though that is how most people acquire the files. As of Feb 2012 the only emulator on Android that requests a bios file is for Playstation and even then it’s only required to increase performance and unlock certain features.
So getting an emulator setup for any given system is done with the following three steps.
You can also feel rest assured that as long as you aren’t distributing large amounts of ROMs through hosting your own site you should be relatively safe from a legal perspective