9. Make sure that the microphone and speaker ports on the bottom edge of the iPhone aren't obscured by anything, otherwise you may sound muffled during calls and speakerphone mode won't be great.

10. Beware that the design of the case may make it hard for the dock connector to connect with docking stations. I kept wondering why my iPhone wasn't charging when docked and I finally figured out that the springiness of the case I was using allowed for a good connection when the iPhone was first docked, but as the material rebounded slowly over the next hour or so, it moved the phone just enough to undock it!

11. Make sure you test whether your headphones or whatever you plug into the earphone jack fits. When used with headphones and accessories that aren't made by Apple, some cases make it hard if not impossible to get a good connection.

12. Make sure that the case doesn't obscure the cameras and flash.

Of the legion of cases I've tried on my family's collection of iPhones, my all around general use favorite has been the . These cases have, as the name implies, an outer hard shell and an inner shock-absorbing liner. The case buttons that overlay the iPhone buttons are molded into the soft liner and protrude through the shell adding very little resistance to pressure thereby more-or-less maintaining the "feel" of the iPhone controls.