I wanted to try and design a media player for a tablet. For one thing, a tablet isn't that big of a screen so the UI has to be non intrusive. Since it is on a tablet people will be using their fingers to interact with the player, so the UI needs to be big enough to operate with clumsy fingers. I wanted people to mainly just use their thumbs, Because they are holding it sideways, I made all the interaction points in the easily accessible spots on the tablet (the bottom corners). To scrub through the video you simply move your thumb from left to right, because the scrubber is curved to match the curved path your thumb moves from left to right.
I had several ideas to design the media player off of. Flip UI being a media player that was basically built out of paper, you could fold the player to reveal the user controls. Shrink UI simply shrunk the player to reveal the media controls under the player. I ended up going with a form of the radial UI because I felt there was a direction to go with a UI built around the movement of your thumb, so you don't have to move your hand too much. making navigating the media very easy.