So you would like to make your phone MagSafe compatible? The InfinaCore MagicMagnet has you covered. It is a silicone accessory that attaches to the back of your phone. It ships with black and white magnets. You can use it with Samsung and Pixel phones.
MagicMagnet features a 1800 gauss magnet, which is much stronger than 400 gauss MagSafe magnets. You can use this to attach your phone to refrigerators and metal surfaces.