Using Google’s Gears platform, the new capability enables users to maintain a local cache of messages which is kept synchronised with Gmail’s servers when and if connectivity becomes available. Features include the ability to read, star and label messages as well as queue messages to be sent from the user’s outbox. Google’s claiming they’re able to provide a near-live representation of the service when in offline mode.You can read Kevin Tofel’s initial impressions of Gmail’s offline support over at jkOntheRun.

Gmail has long offered offline support through standards-based POP and IMAP interfaces, enabling users to wire their Gmail to their email client of choice. Personally, I utilize Gmail’s web interface when connected and, when offline, access my mailboxes through a combination of Gmail’s IMAP support, coupled with Apple Mail. Though these features have worked well historically, even IMAP folders don’t map cleanly onto Gmail’s folder structure – and there can be minor glitches in synchronisation.

What Google is promising is the ability to work in the same environment and with the same features, both offline and online, a precedent that casts some doubt over the usefulness of rich Internet clients, such as those built on Adobe AIR.

Interestingly, buried in today’s news was the announcement that, Hotmail is finally adding POP3 support – eleven years after Microsoft acquired the service! We’ve previously covered how it’s possible to jailbreak Hotmail data and transfer messages out of the ageing app.

If anything illustrates why data portability is important in web-based services (and for web workers), it’s this reality; Microsoft passed an 11-year sentence of imprisonment on its users’ personal data and is now paying the price with a 5 percent decline in its user numbers.

Read more at the Official Gmail blog and Hotmail Now Does POP3.

Have you tried Gmail’s offline support?

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