I dismantled the TomTom iPhone ball mount and removed the microphone base (which would effect the standby compass). Later I'll machine up a Delrin socket to match the original rotating design.
Rotating the phone allows access to all the application functionality (radar etc) in the vertical or horizontal planes without obstructing switches and instruments. I don't have ADF, so I need to be able to phone the AWIS for ATIS information. It will also allow me to make calls through the headset and listen to iPod music ... on those rare occasions when I have spare brain cells during flight !!