Activating Gmail's offline mode will allow you to view and compose emails when you don't have access to an internet connection. However, offline mode is only available if you are using the Google Chrome browser and have download the Gmail Offline beta app.
How To Activate Gmail Offline
To get started, open Google Chrome, go to the Chrome Web Store, and search Gmail Offline:
Select Add to Chrome in the upper right hand corner of the screen and in the next window select Add app to complete the set up:
You will the be directed towards you personal Google apps page where you will find Gmail Offline. Click the Gmail Offline icon to continue the configuration. On the next page, select Allow offline mail and then click continue to complete the installation and access the app:
How To Launch Gmail Offline
To use Gmail Offline, open Google Chrome, click on the Apps menu, and then select Gmail Offline.
With Gmail Offline, email synchronization is automatically achieved when your device is connected to the internet. The application automatically downloads and saves your received emails for offline viewing. You can also compose emails offline to be sent when an internet connection is available.