Offline Gmail by Google

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Google will begin to offer browser-based offline access to its Gmail
Webmail application, a much-awaited feature.

This functionality, which will allow people to use the Gmail interface
when disconnected from the Internet, has been expected since mid-2007.

That's when Google introduced Gears, a browser plug-in designed to provide
offline access to Web-hosted applications like Gmail.

Gears is currently used for offline access to several Web applications
from Google, like the Reader RSS manager and the Docs word processor, and
from other providers like Zoho, which uses it for offline access to its
e-mail and word processing browser-based applications.

Rajen Sheth, senior product manager for Google Apps, said that applying
Gears to Gmail has been a very complex task, primarily because of the high
volume of messages accounts can store. "Gmail was a tough hurdle," he
said.

Google ruled out the option of letting users replicate their entire Gmail
inboxes to their PCs, which in many cases would translate into gigabytes
of data flowing to people's hard drives. It instead developed algorithms
that will automatically determine which messages should be downloaded to
PCs, taking into consideration a variety of factors that reflect their
level of importance to the user, he said. At this point, end-users will
not be able to tweak these settings manually.