The bracket (vergleibar with the Navi-holders) fixed by means of a large suction cup to the car window and sucked firmly by a lever mechanism to the disc. In addition, the sucker is equipped with an adhesive coating so that the holder receives enough adhesion to hold the phone. The coating leaves fortunately no unpleasant tracks on the disc.
During the practical test, the mobile phone has been dropped only once. However, reason for this was probably ehr the dirty windshield of the car.
One can hold so: In saubererm underground the holder will keep 100%!
The service is totally foolproof and it should work through the flexible sliding mechanism with any cell phone (it works even with mobile phone shell).
The corresponding pressure points that grip the phone, and to any required front and slide back and leave, because the rubber coating, no scratches on the phone.
The mobile phone can be either an upright, and used crosswise. With a ball joint, the holder is completely flexible in the angle setting. It should however be noted that the mobile phone in the holder may be 100% can not be operated when the buttons are located on the side of the phone this through the support (partially) obscured (by my Sony Xperia Z3 compact are the heads: on / off and volume up / down). However, since I attach the phone only when navigating in the holder, and then I do not need these functions, which is not a limitation for me. After all, these are a universal product and therefore it is not 100% tailored to each device.
Conclusion: It is a very reliable product, which has ensured that I now can use as a full navigation system, and my phone is very flexible, which means to me: every 2 years a new phone, but the holder remains! If that goes with all accessories so, you would save a lot of money.