It proposes all the necessary tools to capture, collect, process and analyse traffic data . Yes it has an API, yes fancy reports, segments, dashboards and goals, yes also to custom variables, …
Although I have immense respect for the product team behind Google Analytics, I must admit that Piwik brings three features that are unmet in Google Analytics.
1. Data ownership and control
Piwik's best value is when it's self-hosted on a controlled server. it then provides full control over the location, accesses, life and death of visitors data . A must-have for many organisations on the Old Continent.
2. Single path analysis
Piwik supports single user path analysis through its visitors profile feature, a feature most competitor solutions don't provide. Single user path analysis is often the only way to get a lively picture of individual customer behaviours on a website, i.e. to get beyond the statistical representation of the behaviour flow .
When done correctly (i.e. when anonymizing visitor's IP), single path analysis is respectful of privacy.
3. Content performance analytics
The web continuing to evolve from static pages to a fluid sequence of content moments, the measurement of content performance will become more and more important.
Piwik proposes a quite simple and elegant solution for content performance, something that in other solutions is rather considered as advanced practices, when not dirty hacks.