Google has added an offline capability to its GMail/Google Mail service, providing a welcome new option for users when internet connections drop out or are not available.

Designed to work with both Standard and paid-for Premier Editions of the Google Apps suite, the new features save data to a cache on the local drive when users are off the connectivity grid, allowing users to read, star, label and archive messages. Composed messages will sit in the Outbox until the connection is restored, then be sent automatically. There is even a “flaky connection mode” that caches data in offline mode and syncs online in the background.

“It’s something business users have been asking for some time,” Dave Armstrong, product marketing manager for Google Enterprise. “Some people have been using other email clients and routing through to Google Mail, but this allows them to work in areas where online capability is not there or is intermittent.”

The move is the latest station of the cross for Google’s Gears platform that has already provided an offline function for Google Docs and third-party apps, and Google plans to add an offline read-only function for its Calendar “in a few weeks’ time”. The offline additions might assuage the fears of some businesses that web-based services are fine when you have a reliable and highly available link, but as useful as a bucket with a hole when you don’t.

The offline mail capability is currently only listed as a Labs project, meaning that it should be treated as pre-release software.

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