I wrote a quick sample app that utilizes the step counter. It acts like a simple pedometer, registering for the sensor events when it starts, and updating the UI with the latest step count whenever a new event is returned.
This updating won’t be in real-time, as the system batches up events. The code currently specifies SensorManager.SENSOR_DELAY_NORMAL as the update frequency – this amounts to 200000 microseconds, or 5 updates a second (should be good enough, even if you duct tape your phone to a cheetah).
I’m using the TYPE_STEP_COUNTER Sensor, which dispatches an event with the total number of steps periodically when a new step is detected. The other Sensor is TYPE_STEP_DETECTOR, which fires a timestamp sensitive event with every detected step (rather than the total number of steps detected so far).
For now, this only works on a Nexus 5 running KitKat, since the API was added in KitKat and the Nexus 5 is the first device to ship with a dedicated low-power step detecting chip.
The code is available on GitHub: android-step-counter