Nite Ize

Wraptor Universal Smart Phone Stem/Handlebar Mount, Black

Snug hold of your phone, easy to install on handlebars (zero tools!) and easy to adjust while riding. Does not rattle one bit.

I spent a while looking at reviews of bike phone holders on that Bezos guy's website, and most holders are like 95% five stars "this thing is great" and 5% one star "it smashed my $800 iphone". This one, though, didn't have that 5%. Only maybe annoying thing is that the backing is hard so on rough roads the phone makes a clattering sound against it.