A fairly new tool, https://spiral.ac/  has some very intriguing features.

The four apps in it offer very different ways to engage with and carry out formative assessments.  Of them, two are interesting – Discuss – which for those using powerpoint presentations, allows for students to comment and for quizzes and questions to be embedded.  The other, we’ll discuss more today – “Clip” which is a way to make videos interactive and is very easy to set up.  Simply put, by pasting the URL for a video on Youtube, students then can comment or answer questions on the video as it is played or paused.  It is a very simple process and a demonstration will easily help understand how it works, so get your phones out or go online to try.