A free app for Android, by Rapid Rabbit Game.

If you like tower defense games, then you’re going to love Outdo IO: Alphabet Letter. In this game, you are the last person alive and you have to defend your base. Collect as many bricks as you can and build up your army. Remember, in the most deadly arena battle, only the one who collects the most bricks and builds the tower at the fastest speed can become the last survivor and climb to the top of the leaderboard.

This is a very simple tower defense game that doesn’t require a lot of brainpower. All you have to do is collect as many bricks as you can and defend your base. You have to be quick to keep your defense tower alive.