Then this month, Apple appeared to make the switch from excluded to excluder in the mobile ad market. New policies for the iPhone 4 bar Google and AdMob from selling ads on the device, resulting in a complaint from Google, which was in the unusual position of playing victim.
“Artificial barriers to competition hurt users and developers and, in the long run, stall technological progress,” wrote Omar Hamoui, the chief executive of AdMob.
After Mr. Hamoui’s complaint, the trade commission expanded its investigation of Apple’s practices to include iAds, according to people briefed on the matter who did not want to be identified because of the delicacy of the investigation.
The commission’s inquiry is not the only one concerning potentially anticompetitive behavior by Apple. The Justice Department recently began a preliminary investigation into whether Apple pressured music labels to exclude Amazon.com, its rival in digital music distribution, from certain licensing agreements. And Apple is one of many Silicon Valley companies whose hiring practices are being examined by the department.
The latest inquiry from the commission has raised eyebrows among some antitrust experts, in part because Apple currently controls less than a third of the smartphone market in the United States.
R.I.M., with its BlackBerry, remains No. 1, and phones based on Google’s Android software are quickly gaining acceptance with consumers and application developers. But some said the government was right to be concerned.
“Apple has gotten really aggressive in trying to flex its muscles and trying to take advantage of its position in the market,” said Andrew I. Gavil, an antitrust expert and professor of law at Howard University.
“The question is whether they have gotten significant enough in any of these markets to affect competition,” he said. “The answer appears to be yes.”
While Apple has created a large ecosystem that has made some application developers rich, many are now fretting that the company has too much control over the world it created.
When an iPhone developer at Facebook announced recently that he was moving on because of Apple’s restrictions, the influential technology blog TechCrunch ran a headline saying the person left “over Apple tyranny.”
And when the maker of a popular app pulled out of Apple’s store in frustration over delays in approving a new version, he asked in a widely read blog post, “Was your intent to shut us down by playing the waiting game?”
For Mitchell Kapor, who invests in technology start-ups including developers of mobile phone applications, it brings back memories of confronting Microsoft while running the Lotus Development Corporation in the 1980s.
“The amount of resentment is very, very large,” he said, “and reminiscent of the kind of resentment there was toward Microsoft when it was the platform an app developer had to be on.”