Originally designed for an Experimental Gameplay Project challenge themed around offering the “bare minimum,” Canabalt was a breakout hit in the 99 cents, top ten-orientated iPhone games space despite being priced controversially at $2.99 and never getting higher than 36 in the charts. Semi Secret Software’s Eric Johnson gave a candid post-mortem of the title at GDC’s iPhone Game Summit, closing out by revealing that Flixel, the flash game API used to create Canabalt, is being ported to iPhone for native development, including an Actionscript to Objective-C translator to accelerate Flash to iPhone ports.
Opening, Johnson discussed the influences for Canabalt’s art and design, referencing Flashback, Another World and Prince of Persia, all games which offer fluid and striking character movement, but also revealing the influence of Neil Blomkamp’s District 9, which despite being about an “alien invasion,” featured a “minimalistic story and a realistic feeling.”
In addition, the game was designed to allow players to control the difficulty of the experience subtly. “As you’re playing the buildings are spaced ‘sort of' randomly,” explained Johnson. “As you increase in speed the buildings become further and further apart. However, boxes, office chairs and the other small obstacles slow you down, so you can modify your speed to maintain your comfort level.”
Johnson went on to defend the decision to offer the game in full, for free, on the web. “People expected that would hurt sales, but in our favour there is no flash on iPhone. And the philosophy has been very successful—even if it has been a little expensive in terms of server costs.”
The decision to offer a free version online may also have affected the piracy rate for the iPhone version. With a free version available online, Johnson announced that Canabalt had a very low piracy rate—just 20% when held against the 115,000 sales in five months the title received.
While stating that they were “very happy” with their sales at $2.99, Johnston admitted that when Canabalt reached its highest point in the App Store charts, 36, it was “possible” that if they had cut the price it would have continued to climb. However, “Canabalt isn’t even in the top 100 games at this point, but we’re continuing to make pretty decent money off it,” he said.
Canabalt for iPhone was based on a port of Semi Secret's freely available Flash game development API Flixel—“just what was needed for it to run”—and ported in total in just under two weeks (based on a flash project that was completed in five days.) Seeing the potential of a full port, Semi Secret are now nearing a public release of a complete version Flixel for iPhone which includes a “rudimentary” Actionscript 3 to Objective-C translator, intended to accelerate iPhone ports of Flash-based Flixel games. “It won’t translate just any Flash game,” explained Johnson, “and it doesn’t do 100% compatible code, but it gets you 90% of the way and will hopefully get the whole way soon.”
Johnston concluded by revealing that that the upcoming Gravity Hook HD has been developed from the ground-up using Flixel for iPhone, and a private beta will soon begin for interested developers who contact flixel@semisecretsoftware.com.