What is Zello Zello Walkie Talkie is an application which allows you to call any of your contacts (who have also installed Zello) virtually converting your Android terminal into a Walkie Talkie. The only thing you need to use is, of course, will be a capable WiFi network. Besides being able to make real time calls, Zello APK will let you leave audio messages to any of your contacts for them to receive them as they become available. This way you can use Zello as a messaging system, leaving notes for our friends our even ourselves. The application, in any case, will show you a list of your contacts with everyone
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