Actually, there was such a project that was made specifically for smartphones. It also has been tested and works on the Raspberry Pi, so I don't see why not it wouldn't work for the Parallella board.
It's called "Casetop", and you can check it out at
http://livi-design.com/.
It originally started on Kickstarter but failed (you can probably still find it on Kickstarter too), however they are still taking preorders on their own website with the help of external funders. You should definitely take a look at it.