Great sum up and a lot of good advices based on the Lean Startup. They say Facebook is now crowded and it's almost impossible for an indie to just have viral success anymore so how did they obtain viral success outside of facebook/social network in the end?

I love the advices about analytics being key but I still don't understand what these projects use to perform their analytics. Are they all building their own solution or using something like Mixpanel right from the start?