Does Zello work between two phones that are connected to a wireless network but not on the internet?
Zello cannot work without internet access, but if both you and your contact are within one network, the voice will be transferred using the shortest way - WiFi network in your case. Internet will be used only to log into zello network and do some service data exchange, it will be less than 1 kiB per second.
Questions? Submit a new ticket for support-related inquiries.