I don't care. Mostly because we already have examples of what classes were like without them and the people who are reliant on them now will adapt and learn to cope if they're taken away.
Additionally, people only think about what phones could be used for in class that they'd disapprove of, rather than things it might actually be useful for. I've personally had great success with recording lessons/lectures, and being able to refer back to them. This allowed me to ask more questions and take more time to understand the subject. Taking photos of diagrams? Awesome. Having a note document that I could reformat that was legible? Awesome.