I'm one of the founders over at ScrumDo, and we can do exactly these sorts of stats with a very flexible report profile feature.
This feature lets you define a workflow (ie. development, testing) and then get statistics based on that.
From there there are two classes of reports that will give you what you want. Our lead time histogram lets you slice and dice the data for the entire workflow, or just parts of it. So you could, for instance, see how long cards takes to go from Development to Qa, but skip any deployment steps you have.
Then there are three kinds of aging reports which would also help fulfill your requirements. These reports help you understand how long cards sit in a given state.
Relative time spent:
You can find full info or sign up here: http://www.scrumdo.com/
Here's a couple help articles showing off some of the reports we have: http://help.scrumdo.com/help/kanban/report-aging.html