The X-Grip is fiddly and annoying and drops phones. Good if you have Apple stock, I guess.
Ram makes a damn near perfect phone mount, but it can be weirdly hard to uncover. I've used the Quick-Grips on all my bikes for aeons inlcuding all sorts of off-road shenanigans and oopsies on my KLR, not to mention an errant Ford encounter on my Vee. It's cheap, absolutely reliable, quick, positively hangs on to phones with or without a case, and just plain bulletproof. No fiddling when you insert or remove your phone. You can adjust the side fingers so that they don't contact the buttons on your phone.
Downsides are that it's plastic (really good plastic, but still plastic) and looks kinda weird. And the whole Ram ball system looks a little weird in many eyes, although it works wonderfully.
The Quad-Lock sure does look great, and is a nice sleek solution. The Perfect Squeeze stuff also looks great and I know it's inspired near-religious devotion among converts. Both are bloody expensive, though...
For small and medium devices, that which you seek is the RAM-HOL-PD3U
The standard size version of the spring-loaded RAM® Quick-Grip™ phone holder provides a secure fit for a variety of phones and other devices. The adjustable side keepers ensure devices like GPS units and Bluetooth speakers within the listed compatible dimensions will also fit in the holder...
www.rammount.com
Recently I upgraded my phone and I had to move to the larger XL model.
This version of the spring-loaded RAM® Quick-Grip™ holder provides a secure fit for a variety of large phones and other devices. Included is a set of two nuts and bolts to attach the cradle to any RAM® components that contain the universal AMPS hole pattern, including RAM® diamond ball bases.
www.rammount.com