Smartphones have already replaced cameras and calendars for many people - and piles of gaming controllers might be next. A startup called WanderPlayer has developed a technology that turns iPhones (and soon Android phones) into controllers for computer games, no matter whether those games call for a classic controller, Wii-like motion controller, a steering wheel or five other options. Here's how it works: Users download a desktop app and a mobile app. The mobile app lists online games from around the web. Selecting a game from the mobile app menu opens it on the computer, and the two devices communicate over Wi-Fi. It's not an easy technology to make work well. "You could probably build a crude equivalent at a hackathon," says co-founder Ayo Omojola, "but both the user-interaction and performance required for games [as well as] the controllers and console that work across local environments are really difficult and take a while to get right." WanderPlayer has developed a controller without a noticeable delay that it says can work with pretty much any game (so far it's applied the technology to about 150 of them). As is, the product is impressive.