In order to upgrade your app or your account to the premium level, you should first subscribe to one of the available packages. To get started with the purchase process, please launch the app and then tap on the "menu" button on the top-left side of the app. In the opened window, tap on "Go premium" and complete the purchase process by tapping on the "buy" button beside each package.
After your successful purchase, launch the app again and sign in with your email address. This email address will be your premium username. Whenever you want to use your Betternet premium account on any of your devices, you should sign in with that email.
**Note**: Premium service is currently available for all Platforms. So you will have no problems subscribing to other platforms.