Zello - Zello's push-to-talk app redefines the walkie talkie. It's a great push-to-talk over cellular (PoC) alternative for businesses and organizations. Learn more about the best walkie talkie app in the market.
Telegram - Telegram is a messaging app with a focus on speed and security. It’s superfast, simple and free.
NuovoTeam - NuovoTeam Push-to-Talk (PTT) App for Frontline Workforce.
Slack - A messaging app for teams who see through the Earth!
Voxer - Turn your phone into a Walkie Talkie. Don't waste time on phone calls and voicemails.
Cisco Jabber - Cisco Jabber lets you access presence, instant messaging (IM), voice, video, voice messaging, desktop sharing, and conferencing.