Sleep Cycle is is an app created by Maciek Drejak Labs that uses the built-in accelerometer in your iPhone to monitor and record your movements as you sleep. It uses data collected to determine which sleep phase you are in. There are two types of sleep phases: deep sleep and light sleep. The app’s alarm uses the data gathered while you sleep to determine when you are in your lightest sleep phase within a half hour period of when you set your alarm. By waking you up when you're in light sleep you theoretically should feel refreshed. Upon waking up in the morning you are presented with a graph detailing your night’s sleep. The graph will show you how long it took you to get to sleep and the different points during the night when you were in light or deep sleep. You also get a percentage figure showing the amount of quality of sleep you received. After the app has gathered data over at least five days you can access graphs showing you how many hours you slept on certain nights and your best and worst nights of sleep. The alarm has many relaxing sounds to choose from that will gently wake you up. You also have the option of using vibration, snooze and of adjusting your wake up phase. You can use wake up moods to record how you feel when you wake up and add sleep notes to help you track how different activities affect your sleep quality. To use the app you will need to set your alarm and all of your preferences through the settings and plug your phone into your charger and rest it face down beside your pillow, making sure you don't cover it with any thick materials. From my personal experience the Sleep Cycle app does exactly what it says on the tin. I've used it for just over twenty days and have noticed that I do wake up more refreshed. The only problem I have with this app is the need to set it every night – and so I’ve forgotten to do so on several occasions. I would encourage you to try it for yourself and see if it works for you!