That's a cool app!
The closest thing I've been able to find in the iOS world is the Emerald Observatory.
Observatory Clock is very useful too. It allows you tap to set marks for navigation. The only wish I have is that it incorporated solar data rather than martian time. Local apparent solar time (where sun actually is in sky) and sunrise/sunset (which along with moon phase tells you when/how dark night will be) would really be helpful.
The app you show is pretty cool. It tells you:
UTC - Universal Coordinated Time. Very useful for talking with people around the world.
Sidereal time. This tells you where the stars are in the sky. The stars rotate around the earth more quickly than the sun by about 4 minutes. This is because earth not only rotates (23 hours 56 minutes) but orbits sun (adds 4 more minutes to face sun).
Solar time is probably the apparent solar time. Clock time is actually a mean (average) solar time. Primarily because the Earth is tilted relative to its orbit and the orbit is an ellipse (vs a perfect circle) the sun runs ahead or behind clock time depending on time of year. This difference is called the equation of time. This tells us how sundials compare to clocks. This is explicitely given in bottom right corner of app.
The sun azimuth and altitude tells where the sun is in sky on its east/west path and how high (angle) it is in the sky. This last also changes due to tilt of earth. This is called declination and follows a pattern like this:
They are also showing planet postions relative to stars and moon relative to sun around the clock dial.
Net, there are thousands of years of astronomical knowledge embedded in that clock! With it you know the position of the celestial bodies.
I got a Tecsun AM loop antenna and experimented with transmitting the Clock Wave app signal via the phone's audio jack.
Amazingly, I was able to sync all my devices at a distance of 25m inside my house, through one interior wall even, with the devices reporting the signal as full strength. However, it appears the devices must be aligned within a few degrees perpendicular to the plane of the loop. More than 5 degrees outside of that orientation the sync would fail, despite the devices reporting full receive strength of the signal. I couldn't tell that adjusting the tuning dial on the Tecsun made any difference.
I had considered trying to make a larger loop antenna out of ribbon cable, but kind of doubt it's worth the effort, especially if it remains that directional. Ideally it would be nice to have an antenna that was capable of 20 degrees either side of perpendicular, so I could put it at one corner of the house and broadcast the signal overnight and all the devices could sync in place as they normally do.
Wow! I think you have the record now. You made short work of that problem. I wonder how much the price will fall on the clocks/watches if the cuts go through? Maybe these will become steals because people wont know how to sync them.
