Wednesday, January 9, 2013

Sleep Cycle alarm clock

Category: Personal

($0.99; no iPad-specific version) Ever wake up two hours too early feeling alert and rested, then go back to sleep and feel terrible two hours later? Thirty years ago, I proposed an alarm clock that would wake you at the appropriate place in a REM (Rapid Eye Movement) sleep cycle. 

Sleep Cycle attempts to do exactly what I proposed, monitoring your activity while you sleep using the phone's accelerometer, and establishing a pattern to your sleeping. It then wakes you before your target waking time when you are naturally becoming less deeply asleep.  

For Sleep Cycle to detect your activity, you do have to have your phone in bed with you, and because the phone is actually running the app all night, it also must be plugged in to a power source. The instructions advise that the phone be placed under the sheet on the mattress, but I've had a pouch clamped to the headboard that has worked well. A nice feature is that the snooze is activated by simply moving the phone.

Does it work? It's hard to say with certainty, even after using this as my exclusive alarm clock for almost two years. Sleep Cycle does have a nice, gentle and progressive alarm sound, and that may be as important to gently waking you as your REM state. 

Sleep Cycle creates graphs of daily, weekly, and monthly sleep data. 

(Sleep Cycle alarm clock)


  1. How does the phone's accelerometer come into play when you're asleep?

  2. Ah - I've just added a paragraph about that - thanks. You have to have the phone somewhere in/on the bed and connected to external power. Awkward, but I came up with a pretty uninvasive solution.