Anything that requires radio is inherently unreliable. Radio is too easily regulated and controlled.
The only option in a hostile state is to use existing communication channels. Such as encrypted networks (or just vpns/proxies) over regular internet that pretend to be https traffic. This is what works now in China/Russia/etc.








Which ones don’t support it? It’s a very old format at this point. Every Android device in existence can work with it for example.