develop for Windows Phone 7.5 and Xbox LIVE Indie Games

Download the Windows Phone SDK 7.1 for Windows Phone. The Windows Phone SDK 7.1 allows you to create apps and games for Windows Phone 7.5 and 7.0, and is available in English, Japanese, Chinese (Traditional), French, German, Italian, Korean, Russian, and Spanish, and includes productivity enhancements such as an app profiler and an improved emulator. The Microsoft Advertising SDK for Windows Phone is also now conveniently built into the Windows Phone SDK, making it easier to earn money through in-app ads.

After you've joined and become an App Hub member, you'll be able to submit your app or game and then price it for sale, monetize your apps via advertising, or give it away for free.

If you're thinking about including advertisements in your app, learn how two college students and a part-time developer grossed more than $40,000 by integrating ads into their apps, and how Microsoft Advertising drove a 71% higher ad yield than a competitor’s Windows Phone in-app ad solution.

We also have ad monetization best practices and training videos that can help you make money, build, register, and measure your Windows Phone ad-enabled apps.

You also won’t have to worry if your app or game idea will be rejected after you’ve spent time creating it, because we've publicly made available the Windows Phone application certification requirements, a submission walkthrough for Windows Phone Marketplace, and the Xbox LIVE Indie Games Game Submission Agreement for Xbox LIVE Marketplace beforehand.