I have been using MVVM Light for my windows phone app. If you haven’t heard about it, I would suggest you to read about it at mvvmlight and documents. It is a great toolkit and the first Nuget package I always add to my windows phone projects.
For starters, you can also go through following articles,
Recently when I was implementing navigation in my app, I used Messenger as explained in Part 2 and Part 3.
Later while debugging the code, I realized all the viewmodels that registered for GoToPageMessage received the message, but I was expecting only the viewmodel that is associated with the view which triggered the page navigation to receive the navigation message.
Then I went back to Galasoft to read more about Messenger and realized I should not be using Messenger for navigation for my case. And found a really good article about how to navigate using mvvm light
Also Laurent is going to do a pluralsight course on mvvm light which is exciting!