This is neat. Well done RunKeeper! If you recall back in December RK announced that they were giving their RK Pro ($10) version away for free for a month. This led to an enormous surge in downloads and even prompted RK to rework their business model and drop the $10 price tag for the RK app and offer it for free forever. This graph obviously displays this jump clearly.

Click through to the original blog post with cofounder Michael Sheeley’s original commentary.