The video game business is learning to get small. Established game software publishers and startups are busy at the Electronic Entertainment Expo (E3) here with plans to push games onto cell phones, a potentially huge new market with equally daunting challenges. From designing games that play well in five-minute intervals to coming up with revenue strategies that work, mobile phones pose fresh opportunities and problems for the game industry. For starters, there's the hardware. While producers of console and PC games have the ammunition to produce detailed virtual worlds, cell phone developers are stuck with postage-stamp sized monochrome screens and pokey processors. For ZIOSoft, a year-old software company devoted to handheld games, the answer is to rely on programming brains rather than brawn. "We're developing for everything that's out on the market -- current cell phones, 3G, you name it -- and we know what we've got to work with," said marketing director Eric Young. "The graphics we can come up with in an 8-bit environment like this -- it's phenomenal. "In terms of memory, we have very little to work with in these games. But we've learned to be compact and conserve space." Console and PC game developer THQ, which recently formed a wireless subsidiary, would rather wait for cell phones to catch up with the current Game Boy Colour, which shouldn't take long, said chief executive Brian Farrell. "We're not targeting current phones at all," he said. "We think its going to build over the next three or four years." Game designers also have to learn to worth with new time frames. Instead of sitting down for an hour or more to wind through a new level of "Quake", cell phone games have to be digested in brief chunks. "We're making time-killers," said Young. "You're in the airport waiting for your plane for 20 minutes -- that's what we're there for." "Entertainment snacks" is how Juan Montes, vice president of personal communications at Motorola, characterised the approach. "Something the customer takes in a small dose, and it's so tasty you come back for more," he said. "The closest analogy is probably to the arcade business." Because the market for such games extends to anyone with a mobile phone and a low boredom threshold, the content also has to reflect mass tastes rather than the hack-and-slash or role-playing pursuits that appeal to experienced gamers. "This is not a traditional gamers' demographic," said Oren Tversky, business development director for mobile software specialist Symbian. "You really have to think about your audience." One of the keys is to rely on brands the general consumer already recognizes. ZIOSoft has a licensing arrangement with software giant EA to develop phone versions of games such as "SimCity" and "Tiger Woods Golf." THQ is counting on its franchise for WWF wrestling games. "We get to tell consumers, 'You want WWF on your phone -- this is how you get it,' " Farrell said. "If you don't have something distinctive that consumers really want, then it's a commodity, like solitaire. And people won't pay for that." Making money is multi-faceted challenge. Farrell insists consumers are unlikely to be motivated enough to buy and install games on their own, so success relies on convincing cell phone carriers to offer the games as a service. The bonus for the game publisher is a recurring revenue source with messy micropayments handled by the phone carrier. "I don't think people will buy software for their phones," Farrell said. "But if it's a matter of having a few dollars tacked on to their bill for a package of games, they'll give it a try. Which happens to be a great revenue model for us." But Young of ZIOSoft argued that customers will resent having to pay connection charges every time they want to blast a few asteroids. "We feel that one of the important things is that once somebody has paid for a game, they want it on their cell phone to play," he said. "At least for the US market, where people aren't connected all the time, we feel the software needs to reside on the phone." For companies who get it right, though, the potential payoff is huge, expanding the game audience from an enthusiastic minority to a general consumer majority. Graham Stafford, senior manager of content development support for Nokia, noted that his company included a space game on a recent cell phone model and found that 50 percent of buyers were playing it on a weekly basis. "These are not people like you and I," he said. "This is your mother, your sister, your auntie. This is the person waiting for the No. 10 bus." Check out Gamespot UK's complete coverage of E3 here. Have your say instantly, and see what others have said. Click on the TalkBack button and go to the ZDNet news forums. Let the editors know what you think in the Mailroom. And read other letters.