Basic Fisheye for smartphone
I found the results to be decent, but not great. It's difficult to take pictures without having your fingers in the frame, except for the risk of dropping your phone. With a pole, it is the lens that risks to fall down because it tends to move. It certainly depends on the phone. (I have a Fairphone 3.)
A bit complicated to put on and keep in place, but you get used to it. If you want to shoot or have a very specific rendering, you will probably not find it practical, but if you just want to take some nice pictures, I recommend it, it does a basic but honest job.