IMO the mechanics are limited for the following reasons: 1. The buttons take up screen space. You either have to design your game with a touch interface in min

IMO the mechanics are limited for the following reasons: 1. The buttons take up screen space. You either have to design your game with a touch interface in mind (touchable objects) or ensure the action all takes place at the center of the screen. 2. In order to hit a button or make a gesture, you have to obscure your view of the screen. This means soft buttons need to be larger than the size of the average finger tip. Which limits the number you can have on screen. 3. The buttons aren't tactile. Again, this limits the number of buttons you can have since it's hard to differentiate between them without moving your finger and seeing where the button is. Given these restrictions, it's no wonder that certain types of game mechanics have become very popular: parabolic motion games like Flappy Bird or Jetpack Joyride, tower defense/strategy games, swipe gestures (Infinity Blade or Fruit Ninja) or puzzle games like Candy Crush. In fact, the mechanics for these games would likely be very frustrating on a controller or mouse/keyboard. I've played a number of action games on iPhone as well, and the controls just kind of suck. Secret of Mana is only playable because the console version's hit logic was glitchy to begin with so it works ok on mobile. I probably wouldn't have played more than 5 minutes if it weren't for the nostalgia factor.