Strangely enough, offline mode in Gmail is a standalone web app (pictured above) rather than being baked into Gmail directly. Click for larger.
Google announced in a post over at the official Gmail blog that it is bringing offline functionality back to Gmail, Calendar and Docs. The feature had initially been enabled in select Google services via Gears, the company’s proprietary browser extension that was later retired in favor of HTML5. It took longer than expected to re-write the offline functionality in HTML5, though. This was in part because Google had to wait until the World Wide Web Consortium ratified new HTML5 features that allow for local browser storage and other technologies that make it possible for developers to write web apps which sync seamlessly between offline and always-on modes of operation.
Gmail offline will be available today, Google said, and offline for Google Calendar and Google Docs will be rolling out over the next week, starting today. In the case of Gmail, offline functionality is enabled via a Chrome Web Store app dubbed Offline Google Mail. As for Calendar and Docs, clicking the gear icon at the top right corner and choosing the Offline mode lets you view events from your calendars and RSVP to appointments while offline, as well as view your Google documents and spreadsheets. Offline Docs editing isn’t supported yet, but Google is “working hard to make it a reality”.
The question is, will you care about working offline now that mobile/broadband Internet and wireless hotspots have become ubiquitous? (YES!)
Upon installing the Offline Google Mail web app, you can access it by clicking the Gmail Offline icon on Chrome’s New Tab page. This will let you can read, respond to, search and archive your Gmail messages without network access. The extension sports the familiar Gmail tablet interface and will automatically synchronize messages and queued actions anytime Chrome is running and a network connection is available. Later updates will bring more features, such as the ability to customize the amount of email to be synchronized.