Finally, I'm building an app for teachers!
Similar to Educreations and ShowMe, "VirtualBoard" allows a teacher or presenter to broadcast their lecture onto a projector from any device. In addition to free drawing (like the other apps), you can also draw over any website (Eventually any application). This advanced interactivity will save teachers time - allowing them to combine the resources of the web with the personal interactivity of their classroom.
I'm hoping to have a "v1" finished by early march. Stay tuned for updates!