For off-road use to recommend additional safety

The manufacturer recommends that the bike mount to mount so that the Navi / Smartphone is mounted inclined at an angle of at least 30 °. For horizontal mounting of the Navi / Cell Phone Holder can slip out of the bike mount manufacturer.
Since my Navi has blown already made the corresponding holder of HR Richter, I bow with string against which the Navi before jumping out of the bracket (HR 25400 Universal Navi Gripper "One for All"), while the Navi Gripper before Harausrutschen from here rated HR Richter - preserved bike mount for the handlebar type II.