averywrote a review of Harmony MP3/Phone Dry Flex Case with Jack on June 23, 2011
This case fit my iPhone 4 with PLENTY of room to spare. I also have a slider case on the iPhone itself and, still, very roomy. I could fit a cigarette on each side of the phone comfortably. I dunked the Harmony case in the sink for 2 minutes with paper towels stuffed into the case to see if they got wet. They were as dry as when they were put in.
Only "negative" (if you can call it that) is that it's hard to get all the air out of the case when it is clasped shut, so sometimes it's like a deflated balloon when trying to use the phone. But it makes it more buoyant... Either way, this case is perfect for occasions where you want to keep the elements out while still being fully operable.