Apple opened registration for its annual developers conference this summer on Wednesday.

Tickets for WWDC are steep, at $1,599, and available only to members of Apple’s paid developer programs. Passes to the mid-June event, where Apple usually makes some big announcements, are limited to one per person and five per company.

At last year’s conference, Apple co-founder Steve Jobs was on hand — a few months before his death in October -- to announce the iCloud, Lion and iOS 5. This year should, at the very least, bring some more information about Mountain Lion — the new operating system that Apple said in its Tuesday earnings call would be launched in “late summer this year.” Apple has promised that the conference will give developers a “first look at the latest in iOS and OSX.”

WWDC will take place from June 11 to 15, a couple of weeks before Google’s Input/Output conference, which is open to Web, mobile and enterprise developers. The conference, with tickets costing a mere $900 and excitement about the search engine’s Android platform growing, sold out in about a half-hour. Apple’s conference has a history of selling out in a day. According to MacWorld,WWDC 2011 sold out in about 12 hours; WWDC 2010 took eight days.

Apple has been edging out Android among new adopters, according to the latest research from Nielsen, though Android still has a lead in North American smartphone market share overall. For developers, both platforms have their appeal.

Apple’s reach, more standardized devices and customer standing make the platform an attractive one, particularly as the company builds out its lead in the tablet space. In its earnings call Tuesday, Apple said that it now has 600,000 apps in its store — including 200,000 built just for the iPad.

But Apple places some strict limits on its developers — parts of the iPhone and iPad that can’t be touched, etc. — that make Android’s open system more attractive.

Still, Research firm IDC found that developers still favor Apple, with 89 percent of them saying they’re interested in making software for the iPhone and 88 percent expressing interest in the iPad. And interest in Android has been dropping, because the variety of Android devices and systems discourage app makers from wanting to develop on the platform.

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