This web app has a huge potential (internationally) and is developed following a solid architecture. Being strong PEAR contributors we are of course happy to take a look at what helped the footprintapp.com team achieve such a great product. So I went ahead and asked a few questions to Iarfhlaith Kelly from webstrong.

They talk about time spent using the PEAR libraries, how its helped reduce coding and development time and what sort of packages webstrong makes use of (Auth_HTTP, XML_Parser, etc).