http://openvpnandroid.com/board-software-and-its-possibilities/
OpenVPN Connect is the “official” application from OpenVPN Inc. and is intended to be more user-friendly VPN users with minimal technical knowledge. It’s not as feature-rich openvpn for Android, which is designed toward more advanced OpenVPN users.
Openvpn for Android is a no-cost open-source application developed by Arne Schwarzbe, enables users to connect to any VPN service that supports OpenVPN protocol. If your device isn’t compatible with the pre-configured VPN apps available in the Google Play Store, this is an excellent alternative. It’s relatively simple to set up. You’ll need to import the VPN profile files. (The config files are named.ovpn). They can be downloaded from your provider’s site or via live chat support.
When you’ve imported a profile, just tap the server you want to connect to for that server to connect to it. Once connected all Internet traffic is sent through a secure tunnel and directed to the server chosen by the app. You can see the status of your connection as well as details in the Status tab. A kill switch is always enabled by default and will block your Internet connections when the VPN tunnel stops.
The application also offers per-app VPN as well as an all-day-long feature that automatically activates a VPN connection whenever it is opened and continues to operate even after your device goes to sleep or switches networks. This option however requires Android 7.0 or higher, and may drain your batteries more than usual.
