Was looking for the least visible way of mounting my iPhone in my car. There's nice clips from Rennline (ExactFit) but they are expensive considering to purchase in EU. This is a simple modification from the original model by Henkie72 on TV. The clip is slighly angled so the phone faces towards the driver. Should clip on many cars, but I've only tested on BMW Z4 (G29 model), which means it should also fit 3 series (G20) and the like.

You need to glue the two pieces together and you probably also have to fix the original magsafe adapter in the cup with double sided tape to make sure it stays in when grabbing your phone. Hope it works for you.