The iPhoneDrive launched late Tuesday works only on Macs with installed software, and transfers files to and from an iPhone using a Finder-like interface familiar to Mac users. "That's pretty much it," Glen Aspeslagh, who founded ECamm with his twin brother Ken in 2002, said. "It's a very simple niche product that fills a missing feature."

The brothers got the idea for the product, which costs $9.95, from the Apple iPod, which includes software that can make the music player's hard drive appear as another drive on a PC or Mac. "The iPhone doesn't have that functionality, so we thought we'd try to write a program to add the feature," Aspeslagh said.

In the future, Ecamm could add new features to the iPhoneDrive, such as automatic backup. However, the options are limited, since Apple doesn't give developers access to the operating system on the combo mini-computer and mobile phone. "We're not actually adding any functionality to the iPhone operating system. As you know, that's pretty closed off," Aspeslagh said. Instead, Ecamm's software uses the same application-programming interface as Apple's iTunes software to move files back and forth.

Aspeslagh would like to see Apple provide developers with tools that go beyond just using the iPhone browser to run Web 2.0 applications. Apple chief executive Steve Jobs crowed at the Worldwide Developers Conference last month that developers "can write amazing Web 2.0 and Ajax apps that look and behave exactly like apps on the iPhone, and these apps can integrate perfectly with iPhone service."

Aspeslagh said developers aren't buying it. "I don't think anybody believes his spin." The general feeling among Mac developers is they'll have to wait and see whether Apple gets more generous. "I'm sure they've had their share of developers asking them to open up the iPhone," he said.

Ecamm, based in Somerville, Mass., primarily sells plug-ins for Apple's video-conferencing software iChat. The plug-ins include tools for recording conference calls and for adjusting video images.