I've been meaning to write for a while now about Scott Mullin's blog, PowerCycle, as he bicycles solo from Florida to Alaska, and specifically about how much gear his iPhone has replaced. Last night my wife and I hosted four bike tourists on their way to DC, also with an iPhone, so I'll take that as a sign that it's time to write!
Five years ago I spent a year bicycling around North America, using a Handspring Visor Platinum (a PalmPilot clone) for email and journaling. Since wi-fi was not yet commonplace, I plugged directly into phone lines and used a nationwide dial-up ISP for connectivity. GPS was so expensive back then (around $1000) that I relied on maps and the sun for navigation, as people had done for centuries. I didn't have a bike computer, since I figured nobody (least of all me) cared about my maximum speed or how many extra miles I went the wrong way. I didn't have a digital camera, also for reasons of cost; instead I had my film developed to CDs and stopped in public libraries to upload. If I needed to research campgrounds and other amenities down the road, again I had to stop at public libraries to use the Internet, because the Web browser on the Handspring was pretty much useless. I didn't have a blog, just a Yahoo! Group and a Web page I coded by hand. I did have a cell phone, but that's all it was -- not a smartphone.
Contrast this with Scott Mullin's situation. His iPhone is a camera and a GPS and an email client and a blog editor and a full-featured Web browser. If he wants to see the topography of the road up ahead, there's Google Earth. If he wants us to see the topography he's covered, GPS Tracker will map every turn and every hill.
Of course, now that he's in rural Canada, his cell phone coverage leaves something to be desired... I'm guessing the lack of photos in his more recent entries is not because he stopped taking photos. And god forbid anything happens to the iPhone... I carried a spare Handspring (and a full backup of my data) in case anything happened to one, because the equipment was so cheap ($99 refurbished, even at the time) that I could afford to do so. Who can afford to carry a spare iPhone?