At Mix 2010 Microsoft unveiled the first CTP’s of the tools developers can use to build Windows Phone apps. The Windows Phone Developer toolkit can be downloaded here .
The developer tools CTP is a single install which contains the below tools:
- Visual Studio 2010 Express for Windows Phone CTP
- Windows Phone Emulator CTP
- Silverlight for Windows Phone CTP
- XNA 4.0 Game Studio CTP
Please note that you will need the Release Candidate of Visual Studio 2010 for the Windows Phone Express snap-in to work (beta 2 and below are not compatible).