easy mod to secure the phone in the cheap mounting clamp
more securely/prevent dislodging from slack hits.
Reverse (upside down) the vinyl/plastic pull tab on the tension bar.
Place two zip-ties around the bottom rim of the bracket (the phone edge will be behind these).
In effect three claws are created. Beta tested with another skier’s i-phone whom takes slack hits about 4x/set; still has his phone.