iOS 9 improved the battery consumption reporting significantly, now showing you how much screen time each app is getting and how much apps are running in the background. Head over to Settings > Battery. Scroll down to the list and tap the clock icon to the right to see details of how much time it’s being used both actively and passively. What the frak, Facebook? You’re consuming my time even when I’m not using you. Hopefully some developers will be shamed into making their apps more efficient. But I’m probably just being overly optimistic.