It works for me very well on latest iOS. The important bits are you need to turn the key - the side of the stick without writing need to touch the back of the iPhone. Depending on the iPhone this can be different. For instance, for recent iPhones it is behind the notch. I needs a bit of practice, but once you understand it is pretty easy. No need to power it. If the iPhone does not recognize it, you can move it 15-20cm away for 15-20 seconds and then touch it. The important bit is that the key really needs to touch the iPhone.