GameString also relies on compression but takes a slightly different approach. The company’s software runs more parts of a game on the mobile device—mostly the buttons, menus, and other interface components. “The really crunchy stuff is done on the server, and your phone or tablet takes care of the GUI and your interaction with that,” explains Boothroyd. This means that processing on the server can be more specialized, and that existing smart phone games installed on devices as apps can be adapted to use server power.

Perlman says that the approach is interesting, but he has yet to see a powerful demonstration. “It is hard to evaluate,” he says. “World of Warcraft is not a high-action game like a first-person shooter is, and a phone is not large enough for HD graphics.

Boothroyd says he isn’t trying to convert smart phone users into hardcore gamers, but rather to enable mobile games to include powerful 3-D elements. “You could have an episode within a social game like Farmville where you drive the tractor you just bought around an immersive 3-D environment, or add fight scenes to a game like Mafia Wars,” he says. Such features could be lucrative because many users are willing to pay for goods and tools in social games.

However, the limitations of wireless networks pose a challenge to services like those from OnLive and GameString, says Sujit Dey at the University of California, San Diego. Both companies’ demos took place on Wi-Fi connections, not mobile networks, although both claim that a very strong 3G connection would also just about work. “Wireless networks suffer much more fluctuation in bandwidth than wired networks, and also greater variability in latency and jitter,” Dey explains.

To address this problem, Dey and colleagues are working on their own cloud-enabled mobile gaming technology. One feature of the design is that handsets provide constant feedback on the connection so that any changes that might impair the gameplay can be compensated for on the fly. “I have done interviews with gamers and game publishers, and they are very unforgiving,” says Dey, who is in talks with one wireless carrier about deploying the cloud gaming system.

Perlman says that he is also working with mobile operators. “We’re doing experimental stuff with carriers readying 4G services,” he says. “They can do things at their end to ensure enough bandwidth is available.”