I sit here now using one of these ring holders!
I have it attached to the back of my rather large phone, & thanks to this nifty little thing I can use one hand to hold AND type without the worry of dropping my phone.
These are a 2 pack, metal with a hinged ring ( so can have it up to have finger hold or lay it back when not in use. Very strong not lose in anyway.
The back has an adhesive patch that you peel the backing from to then attach to the back of your phone which is VERY strong!
Then that' it ready to use!... also look pretty smart too