Also most standard clip boards you should be able to make work. Glue on non-slip rubber backing, use rubber bands, etc.
Having used a suck-mount, I prefer a knee board.
mount:
- Easily viewed while keeping an eye outside
- Pain to use in turbulence as your arm flies up and down.
Knee:
- Need to look down occasionally to track progress.
- Easy to use in turbulence; just grab it with thumb and little finger and use other fingers to touch screen.