If you’re connected, in the middle of the main screen you’ll see:
“Connected” and an activated power icon.
For Android, you will also see a persistent notification in the Android notification drawer, and a VPN connection icon displayed in the Android system status bar.
For iOS, the connection will be represented with a VPN icon in the toolbar of the control centre screen. You access the control centre by swiping down from the top left corner of screen.
If you’re disconnected, in the middle of the main screen you’ll see:
“Disconnected” and a disabled/inactive power icon.