Claustrophobic, as the name suggests involves playing a game in a space that is collapsing, where the room to play reduces over time. The game makes clever use of the accelerometer built into the Apple devices to allow the player to control the game by tilting the device.
Carefully designed from the beginning, the timing of the game has been set to provide the player with a pace that is fun, challenging, and very playable.
Through successive levels of the game, new features of the game are discovered, adding complexity and challenge as the player becomes more proficient.
Claustrophobic treats the player with bonus lives and powers as they reach higher levels. These in turn allow the player to keep the game going; to build a higher score.
Without Texture Packer the size of the app would have blown out of control. The animation of the ball within this app made heavy use of sprite sheets, as did virtually every visual component of the game.
These days, the ability to automatically create scaled sprite sheets in a single action is a life saver. When I created Claustrophobic, that wasn't there, and it was much more time consuming.
More recent projects have been much easier.
I have used PhysicsEditor for another app, Crazy Bloons and similar to Texture Packer, my development time was much reduced.
With one sprite sheet in Claustrophobic, I found it essential to use the "extrude" option set to 1 because I had some sprites that needed to scale, and join with neighbours and appear seamless.
I also found that to save space on some sprite sheets, using .pvr.ccz format for the images saved a lot of space. You really need to assess the final images on the screen though to be sure.