This is a vey nice article with some good insights and suggestions. Apple chip design team put lots of effort in A series SOC design to conserve power, the using of power gating is very aggresive. But most of the low power design techniques depend on the assumption of burst usage of phones, so the chip has chance to sleep (power gated) in between. When we have new apps like Pokémon Go which is constantly on screen and updating locations and sensors, this is what users want to do. When a user manually launches an app and intensively uses it, there is not much Apple can do to save power. What Apple can do is how to handle the apps in background. When a background app is comsuming too much memory, iOS will kill it silently to free up more space for the active app. Maybe Apple can extend the similar idea to power: When a background app is comsuming too much power, iOS should kill it to preserve battery life.