While most iPhone games support Facebook Connect, there haven't been many which enable true cross-platform gameplay.

Playdom integrated its MySpace game Mobsters with an iPhone client, while French publisher Boostr is releasing an iPhone client for its online game Urban Rivals.

In fact, the only game we can think of that does the Facebook, iPhone and web triumvirate is Iron Will Studios' Outer Empires, and that's still a bit ropey on iPhone.

So, it would seem there's a big opportunity for any technology companies which can plug the gap.

One such is Sibblingz Inc, which has just announced what it calls - deep breath - 'the world's first cloud-based social game framework that enables game developers to quickly design and build social games using virtual goods and micro-transactions for users to access across multiple front-ends'.

Basically, it's cross-platform technology that enables developers to deploy their games to multiple devices and software environments.

Clearly this sort of thing is going to be massive in future as the more people are playing your social game, the more likely you are to drive viral adoption and longterm stickiness, not to mention the ability to extract revenue via virtual item purchases.

Just add up the numbers: 50 million iPhone users + 350 million Facebook users + X billion web users = a lot.

"I am really excited about offering a universal social gaming framework that will let users play the same game with their friends anytime, anywhere," says Ben Savage, Sibblingz's co-founder.

"We believe this is interesting to both indie developers and large corporations who want to deploy their entertainment content once across multiple channels."

Being a bit more technical about Sibblingz's approach, it has a framework that enables developers to choose if they want to support Facebook, iPhone or web, or a combination thereof.

Then there's a common back-end that's located in a cloud server farm to ensure players can access their account from any of the supported options.

In terms of availability, the Sibblingz Platform is already being used by selected private beta partners, although the beta is open for new companies.

And there's no upfront cost. Instead it uses a revenue sharing business model, althought details remain under NDA until the beta ends in Q1 2010. At that point the platform and revenue share details will be made publicly available.

As for the company, it's been operating for two years now within the YouWeb incubator run by Peter Relan, who kickstarted the Aurora Feint/OpenFeint team.

You can find out more about the technology or sign up for the beta at Sibblingz.com.