I have used three options for mounting an iPhone to the bike:
1) RAM Apple iPhone 4 Mount
This mount fits the iPhone well and is very secure. It is not at all waterproof, and doesn't work if you have any kind of case on the iPhone. Still, RAM makes a number of different mounting balls and arms, so that you can always find something that will fit your bike.
2) BioLogic Bike Mount for iPhone 4
The case is well made, and decently tough. You can have a dock cable plugged in for charging or music/data access, and still remain sealed and waterproof. But it is kind of bulky to leave on the phone, so it's the type of case that you have to mount to the bike and then pop the phone into and out of each time. That's pretty easy to do, but still a bit of a hassle. And it means that you can't easily use another case on the iPhone when it's not on the bike, unless you want to keep taking it in/out of that case, too.
3) LifeProof case for iPhone 4
This case is also completely waterproof, but is a smaller profile and has a smooth back, so I just leave my iPhone in it full time. The headphone port is accessible via a small threaded plug, which is a small hassle and might get lost at some point. But if you're running BlueTooth, then you don't need access to the headphone port. And the dock port is accessible under an easy-to-use sealed flip door, although that doesn't remain fully waterproof when open. Still, the dock connector cable plugs up most of that hole so it should be OK in rain on the bike, although I wouldn't go swimming with it that way.
I originally picked up their Bike & Bar Mount
, but didn't want to hack it up and drill holes to mount it on the Beemer. So I stuck that one on the bicycle, and grabbed their GoPro Adapter Mount
. The mounting arm comes off with one easily accessible screw, so that gets bolted to the bike with no big mods.
The LifeProof case and mount has been working fine for me for many miles, in all kinds of weather. I'm happy with it, enough so that I won't upgrade to an iPhone 5 until LifeProof comes out with a case for it.
'13 Dark Graphite Metallic K16GTLD, 24K miles and counting...
'09 Magnesium Beige Metallic K13GT, 60K miles miles and counting...
'02 Mauve Metallic K12LTC, 106K miles and sold
BMWLT#145, IBA# 366, MOA# 111996, SCMA# 24032
All lower 48 states plus Alaska on the K13GT in two weeks . . .
Some people see the gas tank as half empty. Some see it as half full. All I care is that I know where the next tankful is coming from...