问题
I am thinking of making a watchOS2 app that uses the accelerometer. If the app is running in the background, will it still be able to receive input from the accelerometer or CMMotionManager?
回答1:
You are able to access live accelerometer data only when the watchOS2 app is running. You could however access accelerometer historical data, i.e accelerometer data from when your app was in the background.
Watch this WWDC talk for more information: Whats new in Core Motion
来源：https://stackoverflow.com/questions/31361439/apple-watchos-2-accelerometer