I tested the iPhone RAM Mount/Aquabox setup out today on my tagging expedition(s) and it was a partial success.
The upside: the phone's display was visible, the Navigon app worked, and the audible directions were dutifully relayed from the iPhone to the helmet mounted Midland BT2-D headset speakers via A2DP/Bluetooth.
The downside: the ~20 degree weather and constant app/Bluetooth/GPS use made the iPhone's battery life absolutely suck. How bad? Try one hour until it automatically shut off (thankfully after I'd snapped the photos of me at the tag site). It regained some life magically after being warmed up in my pocket but that level is totally unacceptable.
The solution is to power the iPhone off of the bike, of course, but how to achieve this? My bike already has two sets of additional leads coming off its battery terminals. One is for the heated gear's controller. The other is for a Powerlet (aka, BMW-style) connector that currently is unused.
I first thought that I'd string together a Powerlet -> cigarette lighter adapter -> iPhone car cable series of cables and somehow waterproof the whole mess. This seemed clunky, not cheap, and prone to failure given that it'd be exposed to the elements. Thankfully there exists a ready made solution, a 36" long Powerlet -> iPhone dock connector cable with a tiny voltage regulator in-line. Booyah.
http://www.pashnit.com/product/powerlet/wire_ipod.html <-- first product
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Needless to say one is ordered. With this cable then my iPhone GPS solution (Navigon + RAM Mount/Aqua Box + Midland BT2-D) is actually pretty decent! It has multiple waypoint capability with savable/retrievable complex routes, audible directions beamed to my head, a waterproof handlebar mount with power, and is not in any way dependent on cell reception (all maps live on the device in its memory). I suppose there is the niggling flaw that I have to take my gloves off and take the phone out of its little waterproof box in order to change any settings.
