R90 sleep assistant

Still worrying about your sleep status? Try R90 sleep method to save your sleep.
-Record your sleep
-Record the cycle completed every week
-Plan your sleep plan
The R90 sleep method is a sports sleep coach used by the Premier League Manchester United, designed according to the biological laws of the human body. This solution helps to solve the sleep problem, can help us eliminate some interference from the outside and the inner world, follow the laws of the body, and sleep better.
Generally speaking, human sleep can be divided into two types: rapid eye movement sleep (that is, light sleep) and non-REM sleep (that is, deep sleep). The two interact with each other. When a cycle is over, we wake up, but we usually enter the next cycle unconsciously. The average length of each cycle is 90 minutes. Sleep quality is not measured in absolute duration, but in accordance with a 90-minute cycle, 35 cycles of sleep per week is the best way to sleep is R90 sleep.
If you usually fall asleep at 12 o'clock and get up at 7:30 in the morning, you have just completed 5 cycles. However, one day you stay up all night to go to bed at 1 o'clock. If you still get up at 7:30 in the morning, you will be in a deep sleep state. Forcibly waking up will not eliminate fatigue but will cause some harm. According to R90 sleep, it should be adjusted to go to bed at 1:30, which is exactly 4 cycles. This APP is able to help you calculate and prompt how to sleep in accordance with the R90 method, and help you count your sleep for a week.
May everyone have a good sleep.
Tip: A 30-minute or 90-minute nap at noon is also counted as a cycle.
Hint: This app uses some functions of the HealthKit framework and needs to be used in conjunction with health apps, and requires permission to read and write sleep data.