People taking a first jump sometimes think that they'll want to make a call from mid-air but this is not a good idea. In the freefall you won't be able to hear the phone nor hold it against 120 mile per hour wind. read more
Steering and landing instructions come from your tandem instructor or, if jumping solo, from your ground instructors on a radio speaker on your harness: absolutely not a time for phone calls and other distractions. Adrenaline can make your hands shaky, too, and you don’t want to drop your phone from 3000 feet. read more
I accidentally took my phone skydiving once. It was in a large pocket with no zip under my jumpsuit. It survived. Jumpsuits usually have a zip pocket for phones anyway. If not you could probably get a rigger to put one on for you. read more