My sister n law had one of these on her phone and my brother decided he liked it so i had to order him one. He said it was easy to put on his phone and has remained on it every since he put it on his phone weeks ago.
He shakes somewhat so this has really helped him keep his phone in his hands, he is an older man and was having a little bit of issue with dropping things, although this isn't just for that it sure has helped with that issue.
You can use this handy ring stand holder for your tablets as well. It also serves as a kickstand to hold your phone and small tablets up with. Pretty handy gadget to be so little and super easy to work with.