Flipgrid is a web based tool which works on Chromebook, computers, Android and iOS devices to allow students to view a question or topics (which can be a video you add or record) and then record a response, and view/reply to their classmates. Grids can be open or locked and embedded into any LMS or website. Topics spark ideas and fuel the conversation. Site gives teachers one free grid. This grid can be edited and used again and again. The paid version provides multiple grids and other useful options. From the University of Minnesota.
Students are able to use the tools they carry with them every day. They love using their camera and viewing the responses from their classmates.
The free version limits replies to 90 seconds (which is enough for most purposes.) It limits user to one grid. The classroom educator price with unlimited girds and many additional features is $65 a year.