Apple's unexpected announcement Thursday that it would let programmers use third-party tools to write apps for the iPhone and iPad may deflate a federal investigation into whether the restrictions were anti-competitive because they made it difficult or ill-advised for developers to write programs for competing smartphones and tablets.

The FTC reportedly opened an investigation into the ban in spring 2010, and, according to app developer Hampton Catlin, FTC attorneys have been talking over the summer to app developers, including himself, about whether the ban makes it less likely that they will make apps for competing platforms such as Google's Android mobile OS and Windows Phone 7 Mobile OS, among others. The FTC has wide latitude to take action against companies it thinks are engaging in unfair business practices.

Third-party development tools, including those made by Adobe, allow developers to write apps once and then programmatically create variations for multiple platforms. Last spring Apple changed its development agreement to force developers to write apps for iOS devices using its own programming language "Objective-C", arguing that third-party tools made apps that weren't as powerful and secure as they should be.

But on Thursday, Apple unexpectedly reversed course.

The FTC thought the ban might instead have been a way to protect Apple's dominance in the burgeoning app market, according to Catlin, who was interviewed by the FTC in early August. Catlin, until recently the lead mobile developer for Wikimedia, also developed the popular Dictionary! app for the iPhone.

After his conversation with the FTC lawyers, Catlin told Wired.com that they were "concerned that by making non–Objective C apps illegal, then you can't develop cross-platform." To the lawyers, Apple saying to developers, "You can't be cross-platform," seemed anti-competitive.

The FTC was also reportedly interested in Apple banning Adobe's Flash, a popular multimedia browser plug-in used for a lot of online video, which Apple says is just too buggy for the iPad and iPhone. But according to Catlin, that reported interest "might just be a red herring" and the FTC was really concerned about the developer rules.

While Catlin said he's not sure regulator intervention is a good thing, Apple's rules did have a personal impact.

"When they asked if I was less likely to develop a cross-platform app now (cooling effect), my answer surprised me .... "yes/" I am less likely to develop a cross-platform app, because I don't want to get pushed off iPhone!," Catlin said. "Its not that Apple has even gone through with the threats, but they are definitely scaring us developers subtly!"

Apple did not immediately respond to a request for comment on whether FTC pressure led to Thursday's reversal. The FTC neither confirms nor denies investigations until they are closed.

Update: Moments after this story was published using Catlin as an anonymous source, Catlin responded to a morning e-mail and agreed to be identified in the story. The story has been updated to include his name and his credentials.

Photo: Apple chairman and CEO Steve Jobs, second left, talks with senior vice president of worldwide marketing Philip Schiller, left, following an event at Apple in Cupertino, California, April 8.

Credit: Eric Risberg/AP

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