The application works by waking the user up within a 30 minute window. During this 30 minute window the application measures the different levels of your sleep from light sleep to deep sleep. The application determines which phase you are in by measuring your movement. Once the application determines you are in a phase of light sleep it wakes you up.

When you place the iPhone in your bed you don’t want it to lock since it won’t allow the Sleep Cycle application to work. The good news is that while the Sleep Cycle application works it shuts down your screen and puts your iPhone into a power saving mode. The application was developed with five months of testing and is now available on the iTunes Apps Store for US$0.99.

Read more at the Sleep Cycle website

Brian’s Opinion

This iPhone application reminded me of a watch I reviewed back in 2007. The watch worked very similar to this iPhone application. How it worked is you wore the watch and it to measured your movement using a built-in accelerometer.

The thing I like about the iPhone app more is that you don’t have to wear it so it’s not as intrusive. Of course, my only fear with putting the iPhone in my bed is that I would knock it out of bed and crack the screen. Still, if you put the iPhone in a safe place I suppose it would be okay.

This application is yet another example of the multitude of uses for the iPhone. Whoever thought of putting an accelerometer in the iPhone was a genius. Of course, the person who thought of the App store is really who put the iPhone over the top and opened the floodgates in regards to what the device is capable of.