I use this alligator style phone holder. It's supposed to stick to the dash with 3M double sided tape but I just added some stick on Velcro to the base and it holds well to the dash mat.
It does rock sideways / vibrate a bit on corrugations but it holds firm.
Only $7.50 delivered!
I previously had a magnetic mount on the air vent but I didn't like it covering the air con/heater or the hazard lights switch!![]()