I have made this many months ago and finally I am putting it up here today so here you go.... If you like the design please vote :)
USE THIS DESIGN FOR YOUR OWN PERSONAL USE ONLY.
There are tons of music app for iPhone but the phone is not ergonomically design to be use as musical instrument. So I wondered it would be so cool to be able to play my iPhone musical instrument app with one hand only.
The main support is on the large eclipse ring which hold the position of the iPhone and the thumb at the bottom to provide extra support on the platform when the fingers touched or pressed on the screen interface. There design comes in two pieces, one is the iPhone case and the other part is the support holder. Because the case is a separate piece from the holder, you can also customise case for other phones like Samsung, HTC, Nokia and etc.
I have updated the design for better support and comfort as attached STL files, the picture you see is the first prototype slightly different from the STL files but the concept remains the same. You may need to modify according to your hand size and shape for better support and comfort.
I have the case iPhone 4 & 4s, message me and I can send you the STL file.
You can check out my other 3D printing ideas at
My youtube channel
https://www.youtube.com/user/danleowiPhone music hand holderv2.stl