How are clients deployed and configured?
With the OpenVPN Access Server product, the best way to deploy them is to have your Access Server installed and working, and with users already set up and working. You give the username and password for the Access Server to a user that needs to connect to the Access Server, and give him the URL of your Access Server. For example your server might be at https://vpn.yourserver.com/ - have the user go there and login with his credentials. The user will then be offered the OpenVPN Connect client software for Windows or mac OS and can download and install that. It will come automatically preconfigured for use and you can simply start the connection from the installed client program.
For Android, iOS, there will be links available to the Play Store and App Store where you can download and install the OpenVPN Connect app from. Then you can use the "Import" function to import a connection profile from a specific URL. Enter the URL of your OpenVPN Access Server and enter the username and password, and you can then use the imported connection profile to start the connection from the installed app.