At first, Jon Trainer had visions of retirement. The software developer had created a game that could be played on the Apple iPhone and iPod touch devices, and sales were through the roof. Users of the iPhone couldn’t get enough of the .99 “Bullfrog Touch,” which pits a ravenous swampland amphibian against a swarm of invading insects. After two weeks, reality set in. “People moved on,” Trainer says. The number of nifty new software-based games, tools and other pastimes came flooding into the online App Store, elbowing aside early entrants.