Glad you like it so far Steve! I would be curious to see how you have it setup for cycling. If you get a chance, please send a screenshot to
info@gauchosoft.com. I'm also glad to hear it hasn't crashed yet. Seasonality Go runs nice and stable on my iPad here, but developers never really know how their apps will behave out in the wild.
The astronomical insert packs a lot of data into a small area, so I'm glad you asked about it. Starting from the center and moving outward, the center circle is an image of the current moon phase. Right now, it's a new moon, so it is almost all black, but give it a few days and you'll start to see something there.
The rings around the moon phase show the moonrise/moonset and sunrise/sunset times in a kind of clock circle. 12 noon is at the top of the circle, and midnight is at the bottom (the numbers mark hours around the edges). The black and white ring shows when the moon is out (white is when it is out). The blue and yellow ring shows when it is daylight (blue is daylight, yellow at night). There is also an orange marker there to show you what time is right now, so you get an idea of how far you are into the day and how much daylight you have left.
The text in the bottom corners are the actual sunrise/sunset times (on the left) and moonrise/moonset times (on the right).
As for the green color, I'm not the biggest fan of green, but green means Go! I'm not sure I'll ever quite look at the app the same again after reading your color comparison.

I was going for a kind of grassy outdoor green, because the app is meant to be used outdoors.
Mike