Just got the ollin yesterday and spent just a little time testing it out. Seems to work fairly well, using this on a Swaro ATS. If you're not careful taking your phone off, the magnetic ring on the objective will pull off a bit, messing up your next shot. I'm likely not going to leave the ring on for normal glassing as it goes on and off pretty easy, and their cover is fairly bulky and heavy.
Concerning the phone case, it does block the other cameras on the phone. However, it comes off really quick. For my phone, the case really isn't much bulkier than the otterbox I normally carry. It's just a little bit wider at the mount interface.
The app flat doesn't work with my S23 ultra, but I just use the pro photo mode and lock the camera that way.
These are just my observations from an hour or so of playing with it on the porch.
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