Sounds interesting, gonna try this framework!
Also, I've got Apex onboard right now, but I'm afraid gestures will not work when I've got another application in foreground. Worth trying anyway.
Thanks for now!
Checked out both suggestions, and none worked well...
Apex - as I said before: Gestures aren't global - works only in main screen
Xposed Additions - there's such option in this module, but i can't see any notifications-related
There's also paid version of Additions but I'm not into buying yet.