Microsoft has started accepting requests for access to the Windows Phone SDK 8.0 Developer Preview program,, the company said in a blog post.
To apply, developers can go to the Microsoft Connect site, and the deadline is Sept. 17 at 5 pm PDT. Developers that are accepted will hear from Microsoft soon after the deadline has passed to get instructions on how to download the Windows Phone 8 SDK and get support.
The objective of the program is to let developers of the most popular apps start optimising them for Windows Phone 8, and therefore it expects the majority of published developers "in this situation to qualify for access," according to the blog post.
Getting developers on board will be key if Windows Phone 8 is to become a success, and limiting access risks alienating developers that are not included in the preview program.
Not all Windows Phone 8 features have been announced yet and the SDK includes comprehensive emulators that give some of that away. Keeping them under wraps will however help generate more excitement, which in the end will help both Microsoft and developers, according to the blog post.
But in the end, the Windows Phone SDK 8.0 -- which is built on top of Visual Studio 2012 -- will allow all developers to build applications and games that target both Windows Phone 8 as well as Windows Phone 7.5. More details on the SDK will be revealed in the coming weeks.
Microsoft is also retiring the name Marketplace for its app store, which instead will be called the Windows Phone Store. It has also made improvements to help users find applications more easily. For example, the Bing search engine is used to supply results.
Microsoft still isn't saying when the company will start shipping smartphones based on the new operating system, but phones like Nokia's Lumia 920 and Lumia 820 as well as the Ativ S from Samsung Electronics are expected to start shipping in November.