In principle, a good holder that sticks stable on the disc and the mobile phone holds good. However, if you have a protective film on the screen, this is pushed through the tight-fitting brackets at the onset of cell phones ... well, since you can not blame the mount yes :) The locking of the different angle is something hakelig, but since you can but you live with, if you do not have to adjust too often, for example, for different vehicles.
