Official Google Enterprise Blog: Using Gmail, Calendar and Docs without an internet connection
The great thing about web apps is that you can access all of your information on the go, and we’ve introduced ways to use Google Apps on a variety of devices like mobile phones and tablets. But it’s inevitable that you’ll occasionally find yourself in situations when you don’t have an internet connection, like planes, trains and carpools. When we announced Chromebooks at Google I/O 2011, we talked about bringing offline access to our web apps, and now we’re taking our first steps in that direction. Gmail offline will be available today, and offline for Google Calendar and Google Docs will be rolling out over the next week, starting today.