Apple iPhone 3G and Android users soon could have access to their Gmail accounts even with no Internet access.

At the Mobile World Congress conference Wednesday, Vic Gundotra, Google's VP of engineering, showed a technical concept of a mobile Gmail application that lets users access their e-mail offline, as well as bring the labeling feature to handsets.

The search company recently enabled its desktop version of Gmail to be functional without Internet connectivity using the Gears application technology. But Gundotra demonstrated a mobile version that's a Web application using the offline data storage standard HTML5.

Google uses the standard for database and cache features, and it lets users browse and read e-mails, label messages, and track e-mail browsing without an Internet connection. The offline application cannot retrieve new e-mails, but it will synchronize with the network once a connection is restored.

Google showed demonstrations of the Web application on the iPhone 3G and the Android-powered HTC Magic, but it's conceivable any WebKit-based browser could use this version of Gmail. Multiple Symbian S60 handsets and the upcoming webOS platform use WebKit as the basis of their browsers.

"You now have an ability to build an app that spans devices as long as that device implements the latest specifications of these modern HTML5 Web browsers," Gundotra said.

Google didn't say when the updated version of Gmail would be available, but it could pave the way for more robust Web-based applications for mobile platforms. Web-based programs generally have been seen as weaker than native mobile apps, but this could provide a way for content producers to get around restrictions imposed by gatekeepers like Apple, Microsoft, and Research In Motion.

Web 2.0 technologies, including Google Gears, are making it easier than ever to mobilize business applications. Learn more about what's available and how businesses are using these technologies to keep their people moving (registration required).