Unit Testing framework for Silverlight Applications

Question

Hello Experts,

   I have one quick query. What according to you is the best Unit Testing framework/ tool available out there to automate the testing process for Silverlight applications?

Most of the blogs I browsed are quite outdated & I believe there must be something that people must be using. 

I think if you have used any testing framework with Silverlight for Windows Phone, Store apps, that too will be useful. 

Looking forward for your responses. 

Thanks & Regards

Supreet Tare