Polleverywhere is an amazing tool to use in the classroom and works on any device. However, in the past, it was difficult to create and disseminate polls from the iPad. This blog posts describes the new Mobile Presenter tool.
This free app seems to be a cross between Keynote, Haiku Deck, and Polleverywhere. Some interesting features including templates and polling capabilities.
GoClass is an interesting, free app for teachers that allows them to create lesson plans, poll students and disseminate information from a single app. Currently, registration is free.