Open-source contributions include matchbook, a platform-agnostic matchmaking service, API, and SDK for mobile applications (think multi-platform real-time gaming), a thread-safe wrapper for Apple's Core Data framework, and a screen-capture utility for iOS. See GitHub for more.
Interested in AI, robotics, sustainable/renewable energy, and Internet-of-Things (IoT) applications. Feel free to get in touch if you have a project along those lines and need a capable technical resource to help make it a reality.