It's an interesting one that's for sure.... you argue distraction, you then can also make a case for any device and its potential to distract (e.g. for BYOD/1 to 1)
you argue photos/privacy, devices can also take photos (in most instances) as well
you argue potential for cyberbullying, devices can also do that
While I support a restriction in terms of technology because jesus I see it on a daily basis the impact of distraction based on device use (the kids here are glued to their devices) I don't think a phone ban is the answer and I would say that this a kneejerk reaction from people in suits who have never taught in a classroom.
For context in my classes we have a HIGH rate of device/technology use along with earphone/headphone use. Our school has a policy that manages it and it's usually well enforced. I rarely see a mobile phone out in the yard etc. and if I do it's quickly addressed. If anything I think iPads/full devices are more of a problem than mobile phones (at least at my school) so the way to handle this is to have strong local policy that is well enforced, not some quickly whipped one that's mandatory for all.
Just an additional note as well - I can understand the issue about independence etc. but if you were caught on your phone at work doing irrelevant activities you'd be sanctioned as well just like you currently are at school. I dunno, I think policy is good when it's done right..... I relate this alot to uniform and the discussions about whether that's an appropriate thing to be doing at school (I think it is, by the way... primarily the work reason as above).
The other concern here is a legal one - a mobile phone is a personal device owned by the student which isn't subject to any sort of acceptable use agreement that has been signed by student/parent etc.. whereas devices are covered by it. Sure a teacher can confiscate a phone but requesting to unlock/view it goes beyond the scope of that. Thought i'd raise that too...... just incase it hasn't been considered by readers

However, I have genuine uses for my phone throughout the school day
Such as? Do you not have a device which can do this? The only reason I can think of that separates a phone and a device e.g. laptop is call capabilities and with that comes a legal issue in terms of school's duty of care. When teachers tell you that contact between parent/student has to go through the office, they're not doing it to be assholes, they're doing it to enact their duty of care requirements.
Despite almost never taking my phone out of my locker, I still don't like the idea of being told what to do. Perhaps that's just the inner rebel in me.
Authority will be around for decades to come, with more significant repercussions for failure to comply (e.g. loss of job/income).