I bought a SPI Belt about a year ago, after constantly borrowing one. This is a *great* piece of running gear. It’s an extremely lightweight belt that can hold a phone while you run. It used to hold my Razr and keys quite nicely. It takes an iPhone well, but I’ve not tried with keys recently. It is also very fast drying and can go through the laundry.
SPI Belts have an insane array of colors and patterns to choose from, so you are almost certain to find one to catch your eye. They are also extremely adjustable, making this a great buy for couples or families to share. Check them out here: http://www.spibelt.com/
I highly recommend this product