Free Technology for Teachers: Use Edcanvas in Edmodo for Visual Organization and Sharing of Resources.
This is a great tool available for free in Edmodo. I have not tested this on an iOS device, but I'm pretty sure that it is flash-based. This allows students/teacher to make a collection of content in a neat slideshow format. This would even be handy for times that you as a teacher have a group of online materials that you would like the students to use for research. It puts it in a neat and orderly format. The link provided shares a little more about it. It even has a nice video tutorial.