Nextav Walkie Talkie Wireless Bluetooth Ptt Speaker and Microphone H3 (Black) - Sends Call Alerts to Android Users with SOS Button ,Works with Ios and Android ISO / Android / Blackberry Apps: Zello, Azetti, Eschat, Voxer, Airptt Etc... Bluetooth push to talk ptt mic/microphone connected to smartphones with an android as well as IOS phone operating system. Can be used with smartphone apps: zello, azetti, ESchat, voxer, airptt, walkie talkie, all talk, tikl, genaker ptt and catcom etc.