Previously, i have used those phone holder with a suction pad that is attached to the windscreen. They tend to fall off when going across rough terrain (like a train track), which brings about much inconvenience and would be a safety concern.
Other phone holders have their pluses and minuses. The aircond vent type is probably the simplest in design, and maybe quite sturdy too. But, depending on the location of the aircond vent, to look at the phone, you may have to look down, which can be a safety concern. Also, i simply don’t like having the aircond vent blocked.
There is the type that is sticks onto the dashboard (with super strong sticker at the base). Obviously you can’t use them in rental cars, and i would worry about damage to the dashboard when you have to remove it. The type that hangs from the rear view mirror is a good idea, since it would be natural glancing at the rear view mirror. However, i discovered another type that seems even better – it clips onto the dashboard. You would be looking more or less straight ahead, and the contraption is very simple.
There are only a few sellers for this type of phone holder, and among them i chose this one because it allows both landscape and portrait mode.
The only downside of this holder is the hassle of having to clip the phone. There is also an alternative clipping method which is easier, but with only portrait mode possible. Then there is also a flexible option that allows you to hang the phone on the rear view mirror, or the sunshade.
Otherwise, if you don’t mind the aircond vent or sticker base type, you could enjoy the convenience of having only to slide the phone into place, plus wireless charging capability too.