Beware of numerous cheap phone camera mounts that fail because they grip the side of the camera exactly where the side function buttons are located.
The key is knowing the position of the phone's side buttons and the finite distance to the eyepiece center relative to where the mount grips the phone.
Another shortcoming is the grip tension is far too much and not adjustable. One way or another, this firmly depresses the side button(s) and the camera fails to operate correctly. Maybe these work with mobile phones other than Apple brand - the key is knowing the position of the phone's side buttons and the finite distance to the eyepiece center relative to where the mount grips the phone.
Units tested are seen in the photos - one that tightens around the top of the eyepiece by turning it and other that uses a screw to tighten the tension around the eyepiece (bottom photo). Both mounts pinch the side buttons on the Apple cell phones with too much force, thus activating the buttons and their respective functions.
The next mobile phone mount to be examined and tested is the Celestron Nexyz. This has adjustments along all three geometrical axes and according to the photos, the gripper is at the lower section of the phone, away from the live buttons.
