Windows Phone 7.1 Developer Tools (code named "Mango") Beta has been released on 24th May 2011.

It contains a noof new features (more than 500) including Internet Explorer 9 and Skype inbuilt in the OSFind more about the features hereYou can use this new Beta Tools to develop applications targeted to both 7.0 and 7.1 OS version.

Remember that, it is still in Beta stage (i.edevelopment stage) and hence you can't use it for production In this post, find the links from where you can download (both Web & Standalone/Offline installer) and install the Developer Tools 7.1 Beta release.
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