* beware a short stem will not be able to accept the support
This phone holder will be very useful for bikepackers too. If you don't have a Garmin GPS, a phone with good bike map software will be a minimum. Especially to cross towns you don't know. A phone on the handlebars when traveling is also very useful for finding a hotel or a campsite in the evening if you have not booked (which you hardly ever do in bikepacking).
If the days are very sunny, be careful not to leave your phone too exposed as it could heat up. If you drive at a certain speed no problem, otherwise it is better to store it in the shade if you are not using it.
Be careful in case of rain, this holder does not protect your phone from water. If you don't have a waterproof phone, store it in your pocket or purse in an airtight freezer bag.
Also be careful not to leave your phone on your holder when you stop to refuel at the supermarket or other! Anyone could then grab your phone quickly ...