Phone Mount
"Having something hold your phone is a 'breath of fresh air' for most wheelchair users. My Phone Mount provides a nice, small 'footprint', sturdy mounting solution." RJ :-)
More...
It's great clamp easily attaches to just about anything, even those hard-to-get places on wheelchairs. The holder itself accommodates almost any smartPhone with a flat back, even if it's in a case (most-times).
These have been extremely popular at the Abilities Expo's that I attend with users claiming they LOVE them :-)
The Phone Mount is the yin, to your yang. You've found what you're looking for.