Among all the tower defense games you can find in the Android ecosystem nowadays, there is one that almost every TD development studio has sunk their teeth into: Castle Defense or Siege is a genre that has gone mainstream lately, and that should be no surprise since it’s the perfect fit for both casual and hardcore players. While people might think it all boils down to hitting that touchscreen as fast as you can to get an arrow or bullet through every moving thing out there, there will always be an Upgrade system, or a full arsenal to be unlocked or bought through IAP.
