Effectively this is an Always-On VPN: Once configured, On-Demand VPN will ensure that a VPN connection is established first before any application communicates with the internet.
First download the Perfect Privacy configuration from the iOS section in the download area (login required). You need to use Safari for that, with other browsers the import may not work. Tap on “Show configurations for download”, choose the location you want to connect to and download the file.
Tap on “Install” on the top right in the window that pops up. You will need to enter the passcode for your Apple device.
Under “General” -> “VPN” you will now see the added VPN connection. You can connect manually by flicking the button on the top. To configure On-Demand VPN, tap on the circled “i” next to the connection.
On-Demand VPN should now be activated. Whenever an application accesses the internet, the VPN connection will be automatically established. In the status bar you should see a “VPN” symbol now.
Of course you can install profiles for multiple locations. Simply repeat the steps above for any other locations you would like to add. That way you can easily switch the VPN server and country.
If you want to delete the VPN connection again, you should go to “General” -> “VPN” and tap on “Delete Profile”. This will make sure that the complete profile including settings and certificate will be removed.