Platequery - Report drivers or contact them with license plate lookups
Eventbrite - Discover Great Events or Create Your Own & Sell Tickets
WWDC app for OS X - An app to view and watch WWDC sessions on your Mac
Attendize Event Ticketing - Attendize is a free & open-source ticket selling and event management platform
Avenue - Event messaging app for WWDC attendees
pretix - pretix helps you to sell tickets for your event in an easy way. It supports multi-lingual events and provides a wide range of features