Dose, between Zephyr and Nougat

Question

I am currently reading official Google Android news about Android 7.0.
I can’t understand something. They wrote Doze to increase battery life by turning off the network and processor when the user locks the screen. But how does it work?

1. I have Marshmallow on my device, and when my phone is locked, I still receive notifications from the application via the network (for example, Messenger).

2. The second thing they wrote, Nougat improved it again due to the processor and network. So what is so different?

Answer 1

Marshmallow , , (, Messenger).

SMS , , "Messenger" ( ). , Doz, push- FCM.

, Nougat, . , ?

"Doze on the go", , . .

Answer 2

Push Notifications , , .

, Spotify , . - , , , , , .

, : , . , , , . , , .

- push- , . .