Iodine - iodine is a free (ISC licensed) tunnel application to forward IPv4 traffic through DNS servers (IP over DNS). Works on Linux, FreeBSD, NetBSD, OpenBSD and Mac OS X.
Gyroscope - Gyroscope is a personalized dashboard for tracking your life.
Swarm - Swarm lets you earn prizes and compete with friends based on the places you go.
CareKit by Apple - Open source software framework for creating health apps
Tooyoo Emergency Sheet - Free & secure, emergency medical information sharing
DNScapy - DNScapy is a DNS tunneling tool. The code is very light and written in Python.