My school was fairly unique
Math and English classes, teachers frowned upon cell phone use. No official rule banned them, however sometimes teachers would answer the phones or if people were caught constantly text messaging, take them away. However a person like me, if I receive a call I just quietly go into the hallway to take it. It was very rare that a students phone would be taken away, if they were it was just for an hour.
Other classes, nobody really cared about cell phone usage. Got away with it