Cell phones, which allow anyone near instant communication with anyone else, are useful to improve efficiency in many areas including transportation. Cell phones can be used to obtain transportation and find out ahead of time if there are any problems, reducing wait times and allowing for an overall increase in efficiency and free time for everyone. There is no reason not to use them this way.
What if your child is stuck on a bus that has crashed? Or they will be coming home from school later than normal? A cell phone can just solve the problem by letting the parent know where the child is, and what to do. School phones can be used, however in some cases a child can be left in an area without a telephone nearby. That is when cell phones are very handy