Voxer - Turn your phone into a Walkie Talkie. Don't waste time on phone calls and voicemails.

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.

Sameroom - Chat interoperability-as-a-service

Walkie-Talkie.io - This completely free walkie-talkie app online allows you to communicate quickly and easily with your friends. Go to the same radio frequency, push to talk and that's it! There is also a mobile iOS version and always 100% free !

Investis - Investis helps companies to use digital channels to increase revenue, enhance employee engagement and influence corporate audiences.

Hibox - Hibox is a mobile app that primarily functions as a platform for collaboration between team members. The software helps maintain communication while a team works on a project, and it provides privacy while supporting the pipeline.