Make harmful objects look harmful

Make it easy to recognize an object. If an image is harmful, make it look harmful. Something looks harmful not only by giving it a specific color, it also needs a threatening shape. Round is not threatening. Make harmful pickups anything but round.

The excellent game Geometry Wars Touch works great on the iPad.

However, the game does not adhere to the guidelines: rotating the device does not rotate the graphics.

This game looks great on the iPad. However, it doesn't adhere to the design goal of any orientation. Another less obvious point is that the game could have been less frustrating if the designers only had followed the principles of natural mapping when calibrating the controls.

Natural mapping: Setting the thumb reach in Settings would be a perfect opportunity to use natural interation. Simply ask the user to move the thumb the way they’ll move during play, and in that way register the reach of the thumb. Currently, the game uses a silly slider.

Sailboat Pro is a great game for the iPhone, also available on the iPad. The game controller is updated to better fit the larger screen. However, the menu interface has not been adjusted to the larger screen.

This is an awesome game with possibly a less general appeal than GWars:Touch. The iPad edition of the game feels a bit rushed; the menus are not at all adjusted for the size of the iPad. The game is exactly the same as the iPhone version, except for better graphics.

Buttons to be operated during gaming should preferably be placed within reach of the players hands, that most likely is holding the device. This means buttons and controls used in-game should be placed along the edges. To have to balance the iPad with a single hand while interacting with the buttons is no good.