Ethan Nicholas, iShoot

iShoot started life as an after-hours project. "It wouldn't have been so bad if I hadn't already had a full time job," says Nicholas, who was working long hours for Sun Microsystems and coding in his spare time. "I was working eighteen hour days during iShoot's development, but [despite that] it only took six weeks from start to finish - and that includes learning Objective C, Cocoa and OpenGL."

When iShoot took off, Nicholas handed in his notice. So does he spend his days rolling around on piles of money, giggling like a loon? "So far, not much has changed," he says. "I spent the past four years working from home, so I'm still at the same desk, the same computer. Honestly, I don't think the magnitude of the change has really sunk in. I haven't even managed to take any time off yet."

iShoot was initially offered as a paid download, but sales were hardly stellar. When Nicholas introduced the free iShoot Lite, though, sales of the paid app went into orbit. "A picture is worth a thousand words," Nicholas says, handing us a graph showing iShoot sales from its release in October to hitting number one on 11 January. Things got very interesting very quickly when the free version hit the App Store.

Does Nicholas have any advice other than offering a free version to promote your paid apps? "How about 'stop producing so much shovelware'?" he asks. "One number one hit generates more money than one hundred bottom-of-the-barrel apps, so I'd prefer to see more people striving for number one and not polluting the iPhone with so much abominable crap."

For now, Nicholas is continuing to improve iShoot - "online multiplayer support is the next big thing there," he says - but he's got plenty of other irons in the fire. "I'm not ready to share any details, but I have two firm game designs I'd like to get cracking on," he says. "They are very different from iShoot, but I think they both have a shot at number one."

Bill Rappos, iSteam

"Steam simulator" iSteam has racked up more than 1 million downloads to date. Just one week after its launch Great Apps, iSteam's developers, predicted sales of $100,000 per month. We asked Great Apps' Bill Rappos, how's that going?

"The 100 grand was only an estimation we made, based on our first week sales. The way things are right now, it seems we are going to hit that target a couple of weeks later than our initial predictions."

That doesn't mean things are going badly, though. "The success of iSteam has given us the luxury to make long-term plans," Rappos says. "iSteam was just the beginning. We are all really committed to our vision, to become a significant player in the App Store providing a wide range of amusing and cheap apps."

Great Apps is barely three months old, and was founded in November by 24-year-old Kostas Eleftheriou and 22-year-old Vassilis Samolis. They thought the App Store would be a great opportunity, but they didn't know anything about Mac or iPhone development - so they bought a Mac Mini and got to work.

It didn't take long. The team's first "test" iPhone app, Comet Buster, was released in November; iSteam hit the App Store at the end of December. "Coding the initial version of iSteam only took seven days," Rappos says. "One of our project selection criteria is to minimise risks by not spending lots of man hours on a single project."

The team is currently brainstorming its next selection of apps. Does Rappos have any advice for other developers? "There is no easy way in the App Store," he says. "It is saturated with apps, which makes it really hard to survive. Our tip would be, keep it simple and be professional."

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Now read 16 totally pointless apps that shame the iPhone

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