It is definitely a gray area.<p>We&#x27;ve wandered through many providers, and while some have ToS against missed calls, the provider we&#x27;re currently using doesn&#x27;t. And we just reached a partnership with a local provider to whom we&#x27;ll pay the residual costs of missed calls, and they&#x27;ll guarantee us the lines. For them, it&#x27;s business, and for us, it&#x27;s not 100% free but much cheaper than regular calls.<p>Regarding the walkie talkie app, yes, that&#x27;s our goal :)
However, one of the parties will need to have an internet connection to send the message. Receiving it is free though.