I thoroughly enjoy using iPads in my classroom. I usually use them for research based purposes. Besides research, I recently gave my GT class a variety of options to label a map of Europe. Their options included - a puzzle map (with varying levels), an atlas, or an iPad.
In their small groups, many of them choose to use the iPad because it's easier to see and they can discuss the locations of countries much more easily than if they all were using an atlas. It began a much more engaging activity for them, seeing that labeling a map can be very dull and low level thinking.
Because my students are use to working on small groups frequently, they have no problem sharing the iPads and sharing their knowledge with one another. The iPads are also an effective motivator because it can be taken away without hindering the activity; however, that is not something that I have had to do. It also forces the students to continue to develop research skills since I do not tell them where they can find the information.