If you have an iPhone/iPod touch you probably already know this App since it trusted the first place of the AppStore in a dozen countries including France and Germany for a couple weeks. If you don’t, well, it’s pretty simple.
Our sleep can be divided into 3 phases (let’s keep it simple):
- Light sleep, subject is very sensible to any exterior movement and still has a lot of muscular activity,
- Deep sleep, stage of real relaxation during the sleep with almost no muscular activity,
- Rapid eye movement sleep (“sommeil paradoxal” in french), kind of light sleep with a better muscular relaxation, typically the “dreaming” phase.
As you can see, the muscular activity seems to be a pretty good indicator of the sleep phases: no activity = deep sleep, a lot of activity = light sleep, in the middle = REMS. Well, a crazy guy decided to correlate the muscle activity with the motion of the bed and found out that the two of them are pretty close to another (I don’t know how your partner’s movements influence the measurements though)… so he created an App for it.
Simple to use: set your iPhone in “airplane mode” (no emissions), launch the app, set the alarm clock to the desired time, put your iPhone face down in your bed and sleep well. After calibrating itself for a couple nights, the App will then analyze your sleep phases and decide when to wake you up so that you are as close to a “light sleep” as possible when it happens.
For example if you set 7:00 am, it can happen that the App wakes you up at 6:30-ish because you are in a light phase at that time. If you are in a deep sleep from 6:30 to 7:00 then the App will wake you up at 7:00 anyway.
The App presents you some kind of graphs statistics with the times you went to bed and when the App woke you up. As you can see, the curves are really different but somehow I was woken up by the App close to the “top” those two nights. Actually, I’ve been using it for more than 2 weeks now and it reached the set time only twice. I guess the app makes some kind of statistical analysis of the phases and calculates on a 30 min period how your sleep should look like.
On the first one above I think the clock was set to 7:00, 6:45 for the one below. And in both cases, the App woke me up when it looked like I was starting to fall asleep again after a light sleep phase. This way, it made sure I wouldn’t be in a deep sleep when the due time came.
Placebo effect or genius App? Well, I sure cannot say… but I must admit I’m pretty amazed with the results. In the last weeks I never experienced this awful awakening where you have trouble opening your eyes, even under the shower. Not that it was a habit of mine but I never felt likely to fall asleep again in the bus nor I felt tired in the morning so… that could be a sign…
Anyway, for 0.79€, I guess you can try it for yourself and be sure to let me know your impressions afterwards 
