ClassCall is a excellent site for creating interactive presentations that reminds me of a cross between 9Slides and a backchannel chat tool. ClassCall allows a user to import a presentation (i.e. Prezi, Powerpoint, etc) and then stream their presentation in real-time to a mobile device. It also has a nice feature to ask questions or "poll" an audience which allows educators to assess learning and differentiate instruction. This is also a nice way to "flip" a classroom and create webinars.
I highly recommend checking out ClassCall by clicking here!!!