EDpuzzle was nominated more than any other app.
If you are not familiar with EDPuzzle is a neat tool that allows you to add your voice and text questions to educational videos. On EDpuzzle you can search for educational videos and or upload your own videos to use as the basis of your lesson. EDpuzzle has an online classroom component that you can use to assign videos to students and track their progress through your video lessons. In the video embedded below I demonstrate how to use the main features of EDPuzzle.
EDpuzzle offers a Google Classroom integration. The video below demonstrates how to use that option.
You can see the complete spreadsheet of nominated apps here.