Walking is good for you.
The American Heart Association says "the simplest, positive change you can make to effectively improve your heart health is to start walking." For starters, they suggest exercising 150 minutes a week.
The problem is—how do you know if you're walking enough? What's your baseline?
I've limned my personal struggles with this before, but I have a tendency to spend all day in front of a computer, then pop outside for a quick run and consider my cardiovascular-health job to be done.
I could keep records of my walking with a pen and paper. I could mark the days on a calendar with when I walked and how far. I could wear an activity tracker, too, those popular wrist bands that passively track my body's motion.
But let's be honest: I'm not gonna actively keep these records. I'm just not that type of person. And in my experience, activity trackers often break.
Enter the iPhone 5S* with its M7 co-processor and the Runkeeper app. The M7 collects accelerometer data, which lets it measure how far you've walked, and Runkeeper's "Pocket Track" feature organizes that data. It tallies up the time, miles, and pace, sticking it on the same calendar that shows my runs.
Even when I took a break from tracking my runs—which are in green here—Pocket Track kept passively collecting data on my walking habits.

Perhaps tracking apps like this alone won't solve America's cardiovascular crisis alone—we'll need changes in our city structures, food systems, and work lives to do that—but they're a start. They let us know how far we have to go.
* While this technology is only currently embedded in the high-end Apple phone, it's safe to assume that within the next year or two, it'll be in all phones.
