These are the notes for GoZync 3. Docs for the latest version of GoZync--GoZync 4--can be found here. GoZync 4 is a free upgrade and is highly recommended (hint: it's faster).
How does GoZync deal with time zones?
Irrespective of time zones, GoZync maintains the last sync time on the server. We're not picking winners based on when a field was edited: its last sync wins. Which is usually perfect since a) the whole point of GoZync is to give mobile users only *their* records, and b) you have the option of syncing only the fields that have changed so you don't have whole records colliding. (You can read about how we handle conflicts here.)
However, if you have users in different time zones than the server, you will want to make one change to the stock GoZync integration in order to make sure your users get all the changes since their last sync.
This mod will tell GoZync to store the record's change times according to the server time, which is in line with how we maintain the device's last sync time.