Office Mix - A FREE add-on in PowerPoint that allows you to insert live video, use digital ink, embed interactive webpage and apps, add quizzes and polls, get students' analytics and reports, etc. It is an amazing enhancement. A must see!
EDpuzzle - Cut, add audio tracks, audio notes, questions, or comments to any video. Check students' understanding and/or progress.
Blendspace - Create digital content quickly and easily. Supports student engagement and interaction.