I really did not want anything bulky. I already hate the fact that a case on my slim Iphone makes it bulky. But I dare not go with out. So I really like that the magnet does not really add more bulk. I was able to use the thinner metal piece and it even works through my case (it is a soft silicone case) So this makes me very happy. Again I have a decorative case and really did not want to cover up the design, nor did I want to tape anything to my phone. So I stuck it to the inside of my case and it works great!  No more trying to place my phone in a holder to use the gps. Now I can simply place it on and go.