Storage viewer is an extension meant for web programmers whose applications store data in local storage. This applications allows you to define keys you want to track and display them in a nice and unobtrusive way over the page you are building. Does your application store JSON strings as the value of a key? No problem, as you can define the path(Object[0].Child[1].SomeProperty) to the item you want to track and then you can see the 'SomeProperty' value.