Read original post at Igor Ralic's Blog
When working with a lot of data in apps based on web services (JSON return format being quite common), you’d normally want to cache it in order to make your apps faster and make your users spend less Internet traffic on refreshing which actually isn’t necessary. Also, if the users opens your app while having no Internet connectivity, it’s nice to show him something, even though it’s cached data. It’s always possible to implement your own caching framework, but there’s a nice library already out there called Q42.WinRT which makes it very easy to do the caching.