Phone car mount: which one works and how to charge

Contents

The three mounting types compared Why the phone still runs flat while navigating Heat is the real enemy What you actually need Conclusion

Navigation, music, hands-free calls: in the car the phone runs non-stop. That is exactly why a poor mount and an underpowered charger show up faster here than anywhere else.

The three mounting types compared

Air vent: quickly fitted, the phone sits high in your line of sight, and in summer the airflow cools the device. Downside: it holds badly on soft or vertical slats, and the vent is blocked.
Suction cup on the windscreen: very stable as long as the glass is clean. In summer heat the grip weakens, and some countries restrict objects in the field of view. In Switzerland the rule is: your view must not be impaired, so mount it as low and as far to the side as possible.
Adhesive pad on the dashboard: the most permanent solution, but it leaves marks and cannot simply be moved to the next car.

Magnetic mounts are now the most convenient option because you dock one-handed. They require a magnetic ring in the phone or in the case, more on that in our article MagSafe explained.

Why the phone still runs flat while navigating

Navigation is the hardest continuous load a phone knows: display at full brightness, GPS, mobile data and often Bluetooth as well. Consumption easily exceeds what an old 5 watt USB charger delivers. The phone then does not charge, it only discharges more slowly. A car charger with USB-C and Power Delivery from around 20 watts solves the problem. Which output makes sense is covered in our charger buying guide.

Heat is the real enemy

A car in the sun gets very hot very quickly, and a phone that is charging and navigating at the same time reaches its limit. It then throttles performance, dims the display or stops charging altogether. That is self-protection and not a fault. Even so, constant heat damages the battery. Practical countermeasures: do not place the mount in direct sunlight, use the airflow from the vent and never leave the phone in a parked car. Wireless charging produces extra waste heat, so in summer the cable is the smarter choice.

What you actually need

A stable mount that suits your car, a car charger with enough output and a short, decent cable. On the last point it does not pay to economise, why, is explained in our post on cheap charging cables. You will find mounts and car accessories with us under Car and Mounts.

Conclusion

Choose the mounting type to suit your car, not the brochure: soft vent slats will not take a heavy mount, and a suction cup needs clean glass. When charging, the output decides whether your phone is fuller or emptier after an hour of driving than it was before.

Frequently asked questions

Why is my phone not charging in the car even though it is plugged in?

Because navigation uses more power than a weak charger supplies. With a USB-C adapter with Power Delivery from around 20 watts it charges even while navigating.

Which car mount holds best?

That depends on the car. Suction cups are the most stable but need clean glass. Vent mounts are quicker to fit and cool the device, but they hold badly on soft slats.

Is a phone mount on the windscreen allowed in Switzerland?

In principle yes, as long as your view is not impaired. Fit the mount as low and as far to the side as possible, not in the middle of your field of view.

Does the heat in a car damage the phone?

Constant heat puts strain on the battery. The device throttles itself when it overheats, that is protection and not a fault. Never leave the phone in a parked car in the sun.