Purple Cherry is an emulator in Windows Phone. In old Version it's just a Gameboy emulator, but in a new version, it can play Gameboy Color roms. So I can play my favorite many Gameboy Color game. You can find roms in google.
In Windows Phone,there is free trial for every apps. Or buy in $1.29. Find it in your Windows Phone store.
Update: in new version, finally it can play Pokemon' without a bug at Mr. Pokemon. Try it.
In version 1.5, the bug has been fixed in Pokemon gold and crystal. You can enjoy with Pokemon game in your Windows Phone now. Find some roms in google. :-)
If you found any problem, comment at a program download place. Their apps development team work quickly.