For our group challenge project, we chose a voiceboard tool that Sandra came up with. All of us immediately fell for Gong since we think it would make an invaluable addition to any course. It would be particularly useful in the EFL field as it would provide listening and speaking practice in an invironment where there is normally not much opportunity for the development of these skills. Among other features, it offers the possibility of listening to and responding to text and voice messages. It also allows the participation in group discussions using synchronous and asynchronous chat.
Here's the presentation we put together: