Ahead of an official launch of its next-generation iOS, OS X and watchOS operating systems, Apple on Friday announced it is now accepting submissions for apps compatible with each platform's features.

Announced through its Developer Portal, Apple said developers are now able to submit apps for review built using the Xcode 7 GM and tested on the latest GM seeds of iOS 9, OS X 10.11 El Capitan and watchOS 2.

Apple also sent out an email to developers requesting they submit optimized apps for review ahead of iOS 9 and watch OS 2's release next Wednesday. OS X 10.11 El Capitan is expected to launch on Sept. 30.

The next release of watchOS, iOS, and OS X will soon be in the hands of hundreds of millions of customers around the world. Make sure your apps are optimized for the exciting new features now available for these platforms.

To prepare, build your apps using Xcode 7 GM seed, and test with the GM seeds of iOS 9, OS X El Capitan, and watchOS 2. Read the App Review Guidelines and use TestFlight to get feedback before submitting to the App Store.

The news comes just days after Apple released golden master builds of iOS 9 and El Capitan on Wednesday. GM seeds represent the last step in software beta testing prior to public launch.