Google on Tuesday released a new mobile version of Gmail that runs in a Web browser on the iPhone and Android devices.

Google VP of engineering Vic Gundotra demonstrated the improved Gmail mobile Web app at the Web 2.0 Expo in San Francisco last week and at the 2009 GSMA Mobile World Congress event in Barcelona, Spain, two months ago.

Unlike native mobile applications, which have to be downloaded, there's no software to install. Running the new mobile client for Gmail is simply a matter of visiting gmail.com while using the Web browser in either an iPhone or iPod Touch (OS 2.2.1+), or an Android device.

In a blog post, Google mobile engineer Joanne McKinley explains that the improved speed and the ability to read and compose messages in areas of intermittent connectivity is the result of new browser technologies like HTML5 and Gears.

"The full impact of this new architecture isn't visible yet, but it will enable us to significantly improve performance and quickly roll out new features in the near future," she said. "We're really excited about the potential impact this change can bring."

Google isn't alone in its belief that developing a single mobile application for the Web can provide relief from the pain of coding and maintaining an app across multiple incompatible native mobile platforms.

At the Web 2.0 Expo last week, Jason Grigsby, a VP at mobile Web application developer Cloud Four, made a similar point, arguing that browser-based mobile applications are becoming increasingly capable and can in many cases compete with native applications that have been designed to run on specific mobile devices.

While it might seem that Web-based apps would suffer for being less conspicuous than native apps -- they don't automatically have icons that make them accessible from a mobile phone's home screen -- the issue of visibility can be dealt with. Both Android devices and the iPhone allow users to turn a Web app bookmark into an icon on the home screen.

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