The Guardian also had an interesting article the day before: http://www.theguardian.com/commentisfree/2015/nov/05/put-off-death-by-ambling-about-a-bit-more-whats-not-to-love-about-walking that was a bit more tongue-in-cheek, about how a pedometer is "a small device is now your jailer, minder, boss and mum", and "move[s you] into the steps-bore A-league". I decided to use my Android smartphone instead (saving myself $100 in the process), since the phone has all the same accelerometers, and I always have it on me.
I use both the Google Fit app, and one from a French company, Withings, called HealthMate. Withings makes very expensive hardware like pedometers, bathroom weighing scales and blood pressure meters. Their Android app also lets you manually track blood pressure, pulse and oxygen saturation (and, bizarrely, height - which I'm sure doesn't change that much from day to day, right?) The two apps are usually within a few dozen steps of one another at the end of the day, so I know they are fairly accurate.
There's also an amusing article by Joel Stein in GQ called How to Get a Superhero Body in 90 Days or Less! Enjoy.