For starters, the app would need to be designed specifically for the iPhone—there's no room for half-hearted ports in our pantheon of great iPhone apps. And that app would also have to take advantage of the things that make Apple's mobile devices special—that means exploiting the touch screen, the accelerometer, the whole ball of wax. The graphics would have to measure up, of course, and the sound would have to be superb. Finally, the perfect app would be simple to use—you should be able to tap it and get down to business without too much reflecting about what it was exactly that the developer had in mind when the app was still on the drawing board.

I'm not sure that the perfect iPhone app exists just yet. But the above paragraph comes perilously close to describing Rolando, the alarmingly addictive iPhone and iPod touch game from app-making powerhouse .

Roll On, You Rolandos: In Rolando, you've got to get the circular, fun-loving Rolandos from Point A to Point B without losing them to the clutches of Shadow creatures. Using finger gestures on the iPhone’s touch screen helps control the action.In many ways, Rolando is a classic side-scrolling platform game, in which you move your pieces from Point A to Point B, overcoming obstacles, gathering up items, and avoiding menacing bad guys as you try to reach the finish line. Knock off one level, and you move on to the next challenge.

In the case of Rolando, that means you're responsible for the safety of the Rolandos, little round guys who just want to roll around, jump, and otherwise enjoy the verdant splendor of Rolandoland. Unfortunately, their gambols have been interrupted by invading Shadow creatures—sinister dark boxes whose very touch proves deadly to Rolandos. Your mission is to roll and jump the Rolandos to safety, picking up gems and rescuing drowsy members of the Rolandoland royal family along the way, all while avoiding Shadow Boxes that lumber, fly, and otherwise impede your path.

Fortunately, you have a whole arsenal of finger commands and the iPhone's built-in accelerometer at your disposal. You can tap on a particular Rolando to control it (or better still, use your finger to draw a box around multiple Rolandos to control all of them at once). Tilting your iPhone or iPod touch causes the Rolandos to roll in that direction. (Except for the decadent members of the Rolando Royal Family, apparently -- the King Rolando must be shoved around by other Rolandos, and the Prince Rolando ping-pongs back and forth every time he hits an object, amping up the difficulty of solving levels when royalty is involved.) Drag a finger upwards, and the selected Rolandos will jump. You'll also come across assorted buttons, wheels, elevators, and other doodads, that you can press, drag, or push with a finger to help your Rolandos reach their final destination.