Per App VPN and other network activity When the new Per App VPN feature is triggered, does that VPN connection only apply to those apps, or does it apply to all traffic on the device?

Also, when the connection is triggered by the domain in Safari, does Safari use the VPN for all open pages, or only those triggered by the SafariDomains key?
The VPN applies only to those apps, not all the traffic from the device. See Per app VPN (enterpriseios.com)


  Apps can phone home through a VPN tunnel as soon as they are launched, and send all their network traffic (and only their network traffic) through it. This is controlled by the MDM admin, not the app developer.
  It will use it for all domains. The SafariDomains key specifies only those domains that trigger the VPN connection.
  
  Additional reference - Configuration Profile Reference sections:
  Per-App VPN Payload
  VPN Payload