Best cool feature of Mate 9?

[rimz808]

There are some cool features that I keep finding/liking about the Mate 9. Share some of your findings

1. Split screen.
I sometimes forget that it's available, but when i use it, it's a handy feature and the screen size makes it very manageable.
2. Ability to check Calendar and Notepad while on the call
Well done Mate 9. So many times I am on a call and need access to jot down notes or number. This handy feature is very much used.
3. Knock knock to screen shot
Kinda cool

 

[Dimas de Leon]

Maybe twin apps?

Closing of all apps when screen locks.
Low resolution power saving.

 

[JZ VR]

Stereo+
The speakers get pretty loud
Screen recording
All the fingerprint sensor gestures like pulling down the notification shade and scrolling through photos.