Open Web Analytics is an open source framework that developers can use to integrate web analytics into any application.

It is built with PHP & besides the standalone usage, it has built-in support for WordPress, Gallery & MediaWiki.

OWA comes with 2 APIs:
PHP: which makes it easier to integrate into any PHP application
javascript: for usage in non PHP pages/websites
It has powerful tracking/reporting features like heat maps, multiple websites, Google Maps integration, RSS/Atom subscription tracking &standard ones like:

page views, visits, and unique visitors over time
unique, new, repeat visitors over time
Click-streams – view the actual click-stream of each visitor
Click Tracking – Track where exactly on a web page users are clicking and view clicks by browser type
Click Heat Maps – view a heat map of where users are clicking on your web pages
Visitor Aging – understand the age of your repeat visitors.
Canned and Custom Time Periods – generate reports using pre-defined reporting periods or custom date ranges
Refering Page Analysis – View the title, anchor text, and surrounding text of inbound links from refering web pages
View visits by user agent
Track entry and exit pages
Track pages by custom page type

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