From Mindaugas B on 2014/12/13 20:12:48 +0000
Hi guys, thanks again for the great work!
I’m considering 2 things:
- Stable wake up and go to sleep times contribute greatly to sleep quality. SleepAsAndroid already does a fantastic job at helping achieve this.
- It is beneficial to synchronize our sleep cycle with sun cycle, as it is the most natural “clock”, to which our body is related in many ways.
Currently used timezone or “wall” clock in our phones is not really very good for achieving #2 because of:
- “Daylight saving” time switching twice a year,
- Time zone offset from solar time is different in various locations. That is particularly important when travelling, for example if you have set your alarm clock at 7:00 - this can mean quite different things in various parts of China
It would be very nice to be able to select WHICH TIME I want to use for wake-up alarms and go-to-bed notifications:
- Clock time (current functionality)
- My location’s solar time (http://en.wikipedia.org/wiki/Solar_time):
2.2. Apparent/true solar time,
2.3. Mean solar time. (Not sure which of these is better for the body, probably it’s better to have both and experiment).
Technically, calculation of apparent solar time should not be very difficult, simplest example would look like this:
- Get current location coordinates,
- Calculate sunrise and sunset for given location,
- Calculate solar noon time: solar_noon = sunrise_time + (sunset_time - sunrise_time)/2
- Calculate solar time offset from clock noon: sollar_offset = solar_noon - “12:00”,
- Calculate solar time: sollar_time = clock_time + sollar_offset.
(this simple calculation, however, does not cover Arctic and Antarctic regions, but I’m sure, it is still possible to do…)
Bottom line: this would allow user to easily set stable and precise sleep schedule throughout the whole year, wherever he may travel! 
P.S. Screen/lockscreen widget displaying both clock time and solar time side-by side also would be more than welcome
Copied from original feature request: http://urbandroid.uservoice.com/forums/264867-sleep-as-android/suggestions/6839044-solar-time