We can detect more mobile phones, consoles, etc. in Piwik
We can build a simple plugin that lists all the user agent flagged as "unknown" in the logs. We can then use this tool to add new Operating Systems / Browsers in the related files (https://github.com/piwik/piwik/blob/master/core/DataFiles)
Here's the UserAgent string from an iPhone:
Mozilla/5.0 (iPhone; U; CPU iPhone OS 2_2 like Mac OS X; en-us) AppleWebKit/525.18.1 (KHTML, like Gecko) Version/3.1.1 Mobile/5G77 Safari/525.20
Maybe some integration with URFL could provide an extension of the browser header functionality
see also http://chrisschuld.com/projects/browser-php-detecting-a-users-browser-from-php/ for lists.
one idea from this page: we could execute the code on a list of 100s of user agents and check for the accuracy of algorithm.
I added iphone detection; http://piwik.org/demo/libs/UserAgentParser/test.php
what other widely used phone or system can we add?
I'd add "BlackBerry" to the list.
added support for: windows 7, IE8, palmOS, iPod, blackberry, Android