Rhomobile promises: Build once, deploy to any smartphone

If you’re interested in developing a mobile application but find the range of phones out there to be overwhelming, a startup called Rhomobile wants to help. Not only does its Rhodes programing framework allow you to build mobile applications using HTML and Ruby (much easier than, say, using the Objective C normally required for the iPhone), but your application is then available for iPhone, Blackberry, Windows Mobile, Symbian, and Android smartphones.

In other words, Rhomobile basically brings the “build once, deploy anywhere” goal of web and desktop application developers to the mobile world. Chief executive Adam Blum says the company was inspired in part by pain he was experiencing at his last job at mobile email company Good Technology, where he says more than 200 engineers struggled to put out applications for three smartphone operating systems. (Competitor Visto bought Good from Motorola earlier this year.)

“I can’t imagine doing that with five [operating systems],” Blum says.

Enter Rhomobile. Apps developed using the Cupertino, Calif.’s platform are deployed as native applications on all five systems, and have customized looks to match — for example, a list in an iPhone application will use the iPhone’s scroll wheel. And Rhomobile is officially taking Rhodes out of testing mode today.

Rhomobile doesn’t yet support features that are available on only some phones, such as the iPhone’s multi-touch capabilities. Blum says that’s one of the items on the company’s to-do list, plus developing compatibility with the upcoming Palm Pre.

Those limitations also speak to the kind of developer that probably won’t want to use Rhomobile, namely one who thinks that (say) iPhone or BlackBerry support is good enough. Even after the company adds support for multi-touch and other specialized features, I imagine it will be hard to make an app that both works across five or six platforms and takes advantage of the features of the iPhone or the BlackBerry or the Android in a compelling way.

As for competition, Blum says PhoneGap provides a similar service, but only works on iPhone, Android, and BlackBerry, and requires development on JavaScript, rather than HTML and Ruby. And unlike PhoneGap, Rhomobile focuses (without being limited to) business applications — Blum says he suspects that his company’s customer base will eventually consist predominantly of large corporations building their own custom apps for in-house use.

Rhomobile has raised $1 million in funding from vSpring Capital.