UTunnel has client application for Windows, macOS, iOS and Android platforms (we are working on one for Ubuntu and it will be released soon). It also allows you to configure manual VPN with native OepnVPN client or on your routers.
Popular Support Articles
Configure UTunnel VPN on Asus Router
Configure UTunnel with native OpenVPN client on Windows 8
Configure OpenVPN with Tunnelblick on macOS
Configure UTunnel with native OpenVPN client on Windows 10