Good night's sleep cycles and iPhone

You can download and use a variety of apps from Apple store in iPhone.
Have been attracting attention as one of them is good sleep clock cycle.
Where this app do I have drawn attention.
There are a number of alarm clock apps.
Trying to wake up comfortably with a variety of approaches.
How do we author are you thinking what are cocksure comfortably.
So, this is the emergence of sound sleep clock cycle.
Attempting occurs a fixed time, it will be regardless of the state of the human body, stimulation.
However, there are many people who should be loud, do not wake up easily.
Let me think about medical sleep there.
There is a light sleep and non-REM sleep REM sleep called deep sleep.
People are have repeatedly alternating non-REM sleep and REM sleep overnight.
If REM sleep state, you can wake up to a relatively smooth.
Sound sleep cycle clock is not using this mechanism.
In other words, the alarm clock is moving when you believe that REM sleep state.
Therefore, the time to wake up, I may not be the time you set.
If you can still occur naturally, that's great.
Though alarm clock, is the point where the rhythm of the body, not the time.
Now that you mention it, I think, the more I think it is amazing that people first came up with this app.
Are people who can not get up in the morning and from the time of a child, people wake up soon.
It would also be an opportunity to think about what is the difference.