By AppleInsider Staff

Published: 07:10 PM EST (04:10 PM PST)

Apple on Monday formally invited developers to begin submitting applications written for Mac OS X Lion its new Mac App Store, promising that a next-generation operating system will be released "soon."

"OS X Lion, the eighth major release of the world's most advanced operating system, will soon be available to millions of Mac users around the world," the Mac maker wrote in an email to developers. "Submit your Lion apps for review now so they can be on the Mac App Store when Lion ships this month."

The Cupertino-based company went on to recommend that developers build, test and compile their apps using the Mac OS X Lion Gold Master seed issued earlier this month and Xcode 4.1 for Lion GM seed, which was just released alongside iOS 5.0 beta 3 on Monday.

All indications are that Lion is on track for a release near the end of the week. People close to the matter told AppleInsider last Thursday that Apple is set to undertake preparations for Lion in its retail stores later this week, with a refreshed MacBook Air to follow soon after.

The $29.99 operating system upgrade will launch exclusively on the Mac App Store, marking the first time Apple has attempted an online delivery method for a major release of its flagship desktop OS. Last month, AppleInsider exclusively reported that the company has held back on new Mac models in order to image new machines with a finalized build of Lion.



Lion sports more than 250 new features, some of which are brought from the iPad and iOS back to the Mac. Notable additions include full-screen applications, auto-save functionality, an iOS-style homescreen, application launcher and new multi-touch gestures.

For more on Mac OS X Lion, see AppleInsider's in-depth Inside Mac OS X Lion series.