Not to long ago Microsoft purchased Mojang for $2.5 billion. So it was just a matter of time before Mojang's hit game, Minecraft, came to Microsoft's own mobile platform.
Minecraft: Pocket Edition has been out on iOS, Kindle Fire and Android for awhile now and is now available on Windows Phone 8.1! There is no word yet if there will be a Windows 8.1 app.
Minecraft: Pocket Edition run on phones with Windows Phone 8.1, and not Windows Phone 8, so you'll have to get the update before playing. It also works on phones with only 512MB of RAM, which means owners of Windows Phone's most popular phone, Nokia Lumia 520, is able to play too.
You can go try out Minecraft: Pocket Edition right here for $6.99 (€5.49) via the Windows Phone Store.