Developers may be disappointed next week when Apple (NSDQ: AAPL) lays out plans for the iPhone SDK. Some details are surfacing today on the kit that make it sound an awful lot like a carrier’s walled garden. The information will be especially disheartening to developers who were banking on Apple to be a less restricted avenue to distribute applications to consumers. The rumors were reported by iLounge, who spoke to a number of sources on the condition of anonymity.

The rumored details:

-- Apple will require that all mobile applications be distributed through iTunes. This rumor has already been circulating for some time. It’s surprising that the carriers are OK with this arrangement since often times they can demand a portion of proceeds from the sale of an application.

-- Apple will hand-pick the applications that will be put up for sale. “Our sources confirm that Apple will act as a gatekeeper for applications, deciding which are and are not worthy of release, and publishing only approved applications to the iTunes Store; a process that will less resemble the iTunes Store’s massive directory of podcasts than its sale of a limited variety of iPod Games,” iLounge reported. This is where developers may feel restricted just as they are today when trying to get on the carrier’s deck.

-- The iPhone and iPod Touch will not support accessories. This could limit creating applications that require keyboards and other add-ons.

iLounge also reported that Apple is expected to release a beta version of the SDK next week, with the actual kit shipping in June at Apple’s annual Worldwide Developers Conference event in San Francisco. That rumor is also being reported by Apple 2.0. Additional announcements next week will include iPhone compatibility with Microsoft (NSDQ: MSFT) Exchange and Lotus Notes.

But then why are we surprised? Apple and walled garden: when was that NOT the case?

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