The VBA8 emulator, released over the weekend for Windows Phone 8, allows users to run GameBoy Advance titles on their mobile device.
According to the app's listing on the Windows Phone store, VBA8 allows players to store and run GameBoy Advance titles directly on their phone. The app is available for $2.99, and for those who are skeptical there is a free demo available for download as well.
VBA8 is compatible with Windows Phone 8 only and requires data services and specific screen resolution to run correctly. Publisher "m.k." has also recently released an update for free Windows 8 Super Nintendo emulator Snes8x, improving the emulator's stability when importing and exporting saved games and tweaking timing issues in PAL region games.
Recently a fully-functional version of the Multiple Arcade Machine Emulator was found tucked away in Gridlee, a retro arcade game available through the store. In September 2009 Apple pulled a Commodore 64 emulator from the App Store, and in 2010 added and then removed the iDOS emulator, which ran Windows 3 and a handful of adventure games from Sierra Entertainment. In 2011 Apple again banned an emulator, a standalone version of MAME
[Thanks, Jameseh!]