This may be useful info for other new iPhone X owners. I have my iPhone X in a Spigen Thin Fit case, and I have a rectangular magnetic plate (for my magnetic car mount) between the phone and the case. The magnetic plate is inserted horizontally (not vertically as usual) and as far low as it will go, so it doesn't cover the center of the glass back where the iPhone X has its internal Qi charging coil.
I bought a 3-coil Qi Charger Stand on Amazon for $20, and it charges my phone perfectly with the case and magnetic plate. I can't feel it getting any warmer with or with the magnetic plate.
I bought a 3-coil Qi Charger Stand on Amazon for $20, and it charges my phone perfectly with the case and magnetic plate. I can't feel it getting any warmer with or with the magnetic plate.