Gmail has added another interesting feature to the Gmail Labs family, where it adds a green or red phone icon next to emails, this green phone icons would indicate that is early in the day in the sender’s time zone, a red icon tells you that it is pretty late to call in the sender’s time zone.

Let’s convert this to a real life example, you emailed a client from a different country say United States about a work you were doing for them, now your client emails you back, but when the email arrived while you were sleeping, some of the content in the email confuses you and you need to have a verbal chat with them to clarify your confusions.

But what is the time in your client’s country? Would they probably be awake to answer your call or would you be invading on their sleep? With the Sender Time Zone labs feature, Gmail will show you a green phone icon, if it would be ok to call the other person, translating into working hours for any given time zone.

If you see a red icon, it would probably mean that, it’s pretty late in the client’s country to be making a call, clicking on the message should show you the current time in the sender’s time zone.

This feature will only work if the originating message contains time zone in the header, if you are looking to view the current time from different time zones, take a look at the World Time Zone gadget for Gmail.

To enable this feature, just go to Settings > Labs and activate Sender Time Zone feature.

New in Labs: Sender Time Zone [Official Gmail Blog]