Verso is a great web-based or mobile (iOS/Android) app for creating a flipped classroom environment. It's simple to setup and connect students to your classes and extremely easy to create flips. Each flip connects students with a video, link, or document and an activity for which they are to respond. Once students have responded, they are able to see other respondent's content. In the teacher dashboard, you'll be able to see who has responded and how. Watch this brief video for an overview of the app.