In March, when Apple opened the iPhone up to third-party applications, it yielded little control over the popular gadgets: iPhone applications are subject to Apple's approval and can be downloaded only from Apple's Internet-based App Store.

Now, developers are complaining about what they see as Apple's capricious rejection of promising apps. Some have been turned down because they "duplicated the functionality" of proprietary Apple applications, even though the same is true of notepad apps, stock tickers, and the like available through the App Store. A program from the German developer Dirk Holtwick, which let Web applications access the iPhone's hardware, was rejected for being "of limited utility," while apps like iBeer (left) were deemed useful enough.