OpenVPN Connect is the “official” app from the OpenVPN Inc. and is designed to be more user-friendly VPN users with little technical experience. It’s not as feature-rich openvpn for Android, which is geared towards more advanced OpenVPN users.
Openvpn for Android is a free and open source client created by Arne Schwabe which allows you to connect to any VPN service that is compatible with the OpenVPN protocol. It’s a great alternative in the event that your device isn’t compatible with pre-configured “off the shelf” VPN apps that are available in the Google Play Store. The setup is fairly simple. You’ll need to import the VPN profile files. (The configuration files are named.ovpn). These http://openvpnandroid.com/board-software-and-its-possibilities/ files can be downloaded from the provider’s site or via live chat support.
After you’ve imported a profile, just tap a server in the list and connect to that server. Once connected it will ensure that all Internet traffic is sent through a secure tunnel and directed to the server selected by the application. The Status tab lets you see your connection’s details as well as status. The kill switch is turned on by default. It will shut off your internet connection when the VPN tunnel drops.
The app also has per-app VPN as well as an all-day-long feature that automatically begins the VPN connection when the app is used and continues to run even after your device is shut down or switches networks. The latter however requires Android 7.0 or higher, and may drain your batteries more than normal.