I have an iPhone 4 on my bike. It is mounted in a RAM mount, open to the elements, my sweaty hands, (and drool??!!). It just seems to work. Has done so for 1 1/2 years or so, including an iPhone 3G before that. If it rains I put it in an Ortlieb waterproof flexible holder that mounts onto my Ortlieb handlebar bag. Or I just put it inside the handlebar bag or in my pocket. I did try the Otterbox when I used it on my motorcycle, because I was worried about a fall at 60 mph, but hasn't happened (yet). The RAM mount I use is:http://www.amazon.com/gp/product/B00...K2ZHEJCA2MS5AG