When considering a cell phone cover or other cases for tablets and smartphones, Kevin Purcell writes on Gotta Be Mobile that there are many things to look for to make sure a case will work for a phone user. The first thing Purcell points out is how much protection a case gives a phone.

"Almost every case offers a degree of protection. I don’t use rugged cases like those from Otterbox because they’re too bulky and I don’t like the screen protectors," he said. "However, I have dropped my iPhone half a dozen times and have yet to break one, and that’s because I almost always use a case of some kind. A couple of weeks ago I dropped my iPhone 4S while it was safely housed in an Incase Snap Stand Case and, even though the case broke, my phone did not."

Other keys to buying a great case include functionality, how the case transforms the phone as far as color and design is concerned, what the case costs and how it fits in with the phone or tablet being used.

In writing a list of mobile phone cases for the iPhone, David Carnoy writes in a CNET review on phone cases that no case guarantees protection for a device, especially when it comes to the screen, but it does give it a much better chance of survival.