"Universal fit" in my experience is usually anything but. Admittedly I run a Ollin, but I would have to get a new case to run the On Glass anyways so this isn't really a desirable/beneficial feature to me. Would be curious to see how well it adheres to rubberized cases as well. Ollin also allows you to attach the phone vertically or horizontally for more landscape style shots due to strategically placed magnets. Looks like with the On Glass is still doable but perhaps less convenient due to the way the adapter ring clamps and is orientated. On Glass also looks like it adds a fair amount of bulk just due to the nature of the adapter and 3D printed components. Just some observations.