iOS: There's no shortage of activity trackers out there, but Get Moving does things a bit differently. While it tracks your daily steps and location, it also graphs when you're not moving.
Get Moving tracks your steps like any other pedometer app, but it also shows you where you're not moving and gives you a timer for inactivity to remind you to stand up and move around a bit. All that data is then shown in a daily and weekly graph so you can see how much you're moving around, where you're not moving the most, and how long you're spending sitting around. As you'd expect, the app has a dramatic effect on your battery life, but if you're interested in collecting data about how you move for a couple of weeks, it's probably worth it.