Hipstermatic App
This app is designed to look and feel like a retro camera. You can change the lens and flash on the front of the camera by swiping at them.
Clicking the arrow on the bottom right will flip the camera round and you can use the viewfinder to take a picture.
The film icon will open the camera and you can swipe through a selection of films that will affect the look of the photo. Whilst an effect like this (in this case black and white) could easily be applied and selected from a menu, it makes the app feel more like a camera and makes using the app feel as authentic as the photos look.
iPhone Tetris
The tetris app does away with on screen buttons that show you where to touch. All actions are performed with gestures and swipes. By doing so there is more room for the bricks to occupy on screen.
I personally feel the screen is a little too busy and colourful, it's often distracting.
One useful feature of this game, it displays where the brick is about to fall, it really helps lining up drops.