Get OpenVPN Configuration Files
You should get an email includes openvpn configuration file then tap on 'Download on App Store' to install openvpn client to your mobile phone
Download application from Apple Store for free
Open appstore to install application.
Install the openvpn application.
Open configuration file sent to your registered email
Open your email application and tap .ovpn attachment.
Find openvpn and tap on it.
Add the configuration into openvpn application.
Enter your username and password
Enter "lon.veripn.com" as server address and username/password
Tap on "Allow"
Tap to connect
You can now connect to VPN.