There are a few options you can change that affects the information displayed by the calendar, you can access them be selecting the Settings option from the menu.
Daylight Saving Time: Daylight Saving Time affects the times reported by the calendar, and the position of objects at that time. To be able to for example show the movement of the Sun in day by day during an entire year the DST setting is not automatically turn on/off DST. You should turn this option on/off to match your current locale.
AstroMode: Centers the calendar at midnight instead of noon, because midnight is where the fun is at.
80's Mode: Everybody loves the 80's, this option brings it back so I'm not sure why anyone would like to turn it off. Keep it enabled to bring back the glory days when the Solar System had 9 planets. Check out the tutorials section to learn more. Disclaimer: I take no responsebility for bad hairdos as a result of using this option.
Use sky color in planisphere: When enabled the background color in the planisphere will use the color codes from the main calendar display to indicate the Sun's altitude (day,twilight, night).
After changing your settings use the Save Settings button to save your new settings so you don't have to set them again the next time you visit. The data is stored on your device using web Storage and not on our servers.