https://www.freetech4teachers.com/2019/08/how-to-use-flipgrid-to-create.html

Flipgrid is a free service that you can use to post prompts for your students to respond to with short videos that they record through their laptops, Chromebooks, iPads, or phones. Your prompts and your students’ replies can be kept private or you can make them public. a complete set of Flipgrid tutorial videos available here.

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more on flipgrid in this IMS blog
https://blog.stcloudstate.edu/ims?s=flipgrid