Offline storage for Gmail which was once provided with the help of Google Gears is no longer active at least on Chrome, but Google quickly set the wheels in motion to put the feature back into the market. This time, in the form of an app in Chrome’s Web Store.
To enable Offline access for Gmail, all you’ve to do is install the app titled ‘Offline Google Mail’ from the Chrome Web Store. After installing the app, you’ll get a notification from the tray notifying you about the installation of an offline app inside your browser.
Approve Offline storage for your Gmail (only on your personal PCs!) and you are good to go. The Gmail interface is a bit different (similar to the ones you see on the iPad) and I like it this way! From now on, you’ll have access to a week’s worth of emails and you are free to organize your email labels, delete emails/archive them and pretty much everything except for sending mails when you are offline and all of these activities will be synced to you Gmail account once you get online with Chrome.
I believe you can expect Google to roll out this feature to all browsers in the coming months.
Source: The Gmail Blog