A:AnswerThe included phone holder will only fit most phones or GoPro's mounts. If you have a mount that is threaded like a camera or GoPro, then it should work. Be aware though that it has a relatively narrow base when legs/handle are open so it is not nearly as stable as a normal camera tripod so you do so at your own risks. So, you may want to consider the surroundings and associated traffic.
A:AnswerIt depends on the thickness of the case, but it will usually hold just not as securely as without the case. I remove my case from my 11 Pro Max.
A:AnswerYes. This is actually a normal tripod with a standard thumb screw on the top that cameras and accessories attach to.
To answer your question the accessories have a threaded hole in the bottom.
A:AnswerHi. At the lowest possible height, the 1/4” screw is at the 7.5” mark. It is about 11” total including the clamp when at lowest height with an iPhone 13 in the clamp in landscape.