StoriesOnBoard

One of the most powerful product backlog management tools. Incredibly flexible, versatile, and simple. For designers and pm's familiar with user story mapping and who care about delivering business value through an iterative experience to their customers and users. Furthermore Stories on Board offers two way sync with the most popular sprint backlog tools so no changes to what the development team prefers. Lastly, the team behind Stories on Board is first class, listens closely to their community, and has a long track record of delivering well thought out features and improvements.

Been working with this tool for a few years and in different organisations (I take it along where I go ;-) ). It gives great overview and visualisation and - and - and - it's easy to use (it's inspiring how far you can get without making things complicated for the end user!).