phpOpenTracker is a framework solution for the analysis of Web site traffic and visitor behaviour. It features a logging engine that, either invoked as a Web bug by an HTML image tag or embedded with two lines of code into your PHP application, logs each request to a Web site into a database. One installation can track an arbitrary number of Web sites. Through its API, you can easily access the gathered data and perform complex operations on it (for instance, the analysis of your visitors' click paths).
Log4php is a PHP port of Log4j, the most popular Java logging framework. It supports configuration through XML and properties files (with the same structure as log4j) and custom Configurators. File, RollingFile, DailyFile, Echo, Console, Mail, PEAR::Db, PHP error, Syslog or NT events, and socket appenders are supported. Simple, TTCC, Pattern, Html, and Xml Layouts are supported. It also supports Filters, custom Levels, and Loggers. Internal debugging can be switched on and off. Log4php can be used inside a class or inside a main/sub function.