There is a bug that has been running for a while now. When ever I load or join a world, players do not have a name. They can't be selected when using commands because of this. When someone joins or leave it will say:

   joined the game

   left the game

The player's name in chats will either display with a blank space or it will say, "entity.player.name"

This appears to be a problem on at least three types of android devices.