Download VPN Software
VPN client for Windows
Official OpenVPN client for OS Windows (open source):
VPN client for Mac OS
Free open source OpenVPN VPN client server software for Mac OS X and macOS:
VPN client for iOS (iPhone / iPad)
Free application. OpenVPN Connect is an OpenVPN client version for iOS.
VPN client for Android
Openvpn for Android is an open source client based on the open source OpenVPN project.
It uses the VPNService API of Android 4.0+ and requires neither Jailbreak nor root on your telephone.
VPN client for Linux and * BSD
This release is also available in software repositories for Debian and Ubuntu, Supported architectures are i386 and amd64. For details. look here.