[frankw]

I converted my Samsung Galaxy phone window mount so that it will fit into the radio cassette.

Parts: -
1) Phone mount preferably with a ball joint tilt adjuster bolt
2) An old music cassette held together by 5 small screws.
3) A milk bottle lid or similar to make a plastic washer.
4) A flat square nut as used in metal shelving to fit the ball joint adjuster bolt.

Assembly: -
5) Take apart the window mount to leave you with the phone holder and ball joint bolt.
6) Drill a hole in the centre of the milk bottle lid to make a washer for the ball joint bolt.
7) Put the washer and flat nut onto the bolt and tighten until the phone holder is tight enough to hold the tilt in any position.
8) Undo the 5 screws to remove the cassette tape and other bits that could rattle.
9) Re-assemble the cassette tape but with screws just loose enough to leave a small gap between each half.
10) Drill a small pilot hole into the small gap. The best place for this pilot hole is appox 10mm from the right hand screw as viewed if the cassette were inserted into the cassette radio.
11) Tighten the 5 small screws and remake the pilot hole.
12) Enlarge the pilot hole until enough to take the phone holder bolt firmly. Use a strip of insulating tape if the bolt is too loose.
13) Screw the protruding bolt into the edge of the cassette so that the flat square nut is firm against the cassette. If the bolt remains loose then use silicon glue to hold it firmy.
14) Insert your phone into your new holder, slide the holder the cassette radio and away you go.

You can orientate the phone onto it's long side (landscape) and use the steering wheel controls if preferred.