This support holds very well on the instrument panel (I have not tested it on the windshield), there are very slight vibration when the road is not very good but otherwise everything remains secure. The mobile (iPhone 4) does not slip it in a vertical or horizontal position and is not damaged by the support (rubber small bands through which by cons do not seem to be very well glued. J 'have one that is beginning to take off). The plastic looks for quality and all seems rather solid (except when we put aside the legs to the laptop, we feel that he must not use excessive force on it). Very Satisfied.