Most schools have a ban on cell phones as they feel they are distracting to a student's learning. I agree with this 100% and I wonder if allowing them in the class for educational purposes would cause more issues than it would solve. I've heard of some teachers, more specifically professors, who have used cell phones to get students to text in their answers to an online poll. While this is a good way to anonymously get students to participate, this also gives them the opportunity to use their cell phones in class for non-educational purposes. As far as iPads are concerned, I know there are some fabulous Apps available and it is an incredibly intuitive piece of equipment if you know what you're doing. But there are also some ridiculous Apps available that I would argue have no value whatsoever. And I think it would be hard to ensure that students stay on task, even if they are working in small groups using one iPad. The newness of this particular technology is a little worrisome to me and I'm not sure how I would best use it.
I really like the idea of the SmartBoard but I think it some ways it's a glorified white board. The challenge with that particular technology is using it in a way that is both creative and intuitive, not simply using it because it's there. I haven't had the opportunity to use a SmartBoard in a classroom yet but I would love the opportunity to work with one and find unique ways to incorporate it into my teaching.