Not the first Angry Birds, that was a snowball hit not a first week blowout. Minecraft is paid. I would guess FB Messenger or maybe Google Maps. Or something

Not the first Angry Birds, that was a snowball hit not a first week blowout. Minecraft is paid. I would guess FB Messenger or maybe Google Maps. Or something from China, seems like when QQ releases a core app there's millions who just go and download it.