All of the world timezones (graphically) on your watch.
Select a timezone by touching the top right (west) or top left (east) of the screen. The timezone offset is displayed along the top of the screen - daylight savings is NOT accounted for - std. offset values are used. Zone 1 (east or west, will require 2 taps, it's then 1 tap there-after). Each successive tap increases the timezone displayed, until the max is reached (-10 or +12), thereafter it resets to 0 (blank). Then 1, 2, 3...
Turn zone boundaries on/off by touching the bottom left (health info) of the screen. Zone boundaries are almost geographically correct, rather than just straight lines.
Change the map colour (green/grey) by touching the bottom right (time) of the screen.
The watchface DOES NOT require internet connectivity.
UTC time (centre) is always shown in 24hr format. Your local time (bottom right) is 12/24hr format based on your fitbit profile setting.
Thanks to Nev for assistance with some coding.