I'm sure we have all had issues on our phone and been told it could be caused by an application. I myself am reluctant to believe that at times cause I've had these apps on my phone and not had issues. If you dial *#0*# you can check your camera, speaker, frequencies, sleep mode, vibration, screen dimming, touch screen and many others. If you're having issues with any of these you can easily determine if its the phone or more likely an app. Plus, who isn't intrigued by cool things on your phone. What a neat thing to show off to your friends.