I too use the Kipling waist pack. It's convertible to a crossbody. I used the small Coach crossbody a few times but like the waist pack best. Sometimes I just swing it over my shoulder anyway.
I would love to just carry a crossbody phone holder, but I like to carry a small pack of Wet Ones, a tiny ziploc of Tylenol, a small pack of tissues, my Disney Visa card for the benefits, my compact and lip balm, a small disposable poncho for Kali River, and my iPhone (mostly as a camera). I have a LifeProof case for my phone so I don't worry about it getting wet.
I have two daughters, ages 11 and 13, and they now carry their own stuff in a waist pack, like their iPods, Wet Ones, and autograph books, etc.
I dream of going bag-free one day but I don't see how.