Case-Mate has a reputation for making quality Windows Phone cases and the Case-Mate Pop! for the Nokia Lumia 900 follows in that same tradition. The Pop! is a well built case that fits snugly around your Lumia 900, adds a decent amount of protection, but it may not appeal to everyone. While the one piece case does offer a good amount of protection it also adds a good amount of bulk to the slender Windows Phone.
We've looked at the Pop! cases before with the Samsung Focus and liked what we saw. With the Lumia 900 though, the Pop! adds more bulk to the Lumia 900 (the case seems more beefier) that may detract too much from the Windows Phone for some.
The Case-Mate Pop! has a rubber lining with a hard shell backing. The rubber lining is exposed at the sides of the case providing a nice gripping surface and along the face of the case to provide a bumper to protect the screen. A plastic kick-stand folds into the back of the case that can be used to prop up your Lumia 900 (for video viewing and such).
The Lumia 900 pops into place (hence the case's name) and the fit is tight to eliminate any wiggle room. Buttons are not exposed but rather covered with rubber extensions that work rather nicely. A large cutout is on the back of the Pop! to expose the camera and light. A recess is cut out of the top of the case to expose the micro-USB port and a hole is in place to access the headphone jack.
While the Case-Mate Pop! offers a good amount of protection, it gives the Lumia 900 a significantly beefier feel to it. The Pop! isn't a bad option if you need the added protection but if you like the slim feel of the Lumia 900, you may not like the Case-Mate Pop!. Pocket carry is still possible but the phone doesn't slip inside pockets as smoothly and the added bulk can be a little uncomfortable. Should pocket carry be your style, with the Pop! you're more or less limited to back-pocket or cargo pocket carry.
If you carry your Lumia 900 in a briefcase, purse or backpack, I could see the appeal of the Case-Mate Pop! as added protection otherwise, I can see the thickness the case creates not being very appealing.
The Case-Mate Pop! comes in black/gray and white/gray color patterns. The Pop! is currently running $29.95 and you can find it here at the Windows Phone Central Accessory Store.