Sorry! We don't have a one-time purchase method in the current version.
Because of the AirScreen is Cloud-based app, the core features of AirScreen MUST be supported by our server clusters when you are using them. Therefore, we have to spend the high cost on our server clusters and broadband every month.
When you use an app to mirror (or cast), some of the multimedia resources requested by the app need to be parsed and processed by our server clusters.
Thanks for your understanding and support.