iOS: There is no shortage of activity monitors in the iTunes App Store, but Moves for iPhone works a little differently. It tracks your daily activity without the need for an external device or extraneous social features.
Moves is a simple pedometer that tracks how many steps you take a day, but it can also automatically differentiate between walking, running and cycling. It also tracks your GPS data so you can see where you go throughout the day, how you get there and how long you spend there.
The app runs in the background automatically, so if you take a walk and then jump on a bicycle, there's no need to open up the app and change any settings -- Moves knows what you're doing. At the end of the day, you can view where you've gone (and how you got there) in a simple timeline.