Simple Walkie Talkie is a free Android app developed by Chirco Software. As the name suggests, it brings back the classic experience of using a real walkie-talkie. The app also includes a Baby Monitor mode. Simple Walkie Talkie supports Wi-Fi and Bluetooth, making it easy to use for both personal and professional communication needs.

To use Simple Walkie Talkie, both users must install the app and connect to the same Wi-Fi network. Alternatively, Bluetooth can also be used to connect between two devices. The app is simple to use - press and hold to start transmitting, release to stop. However, note that you cannot receive audio while you are sending audio.

Overall, Simple Walkie Talkie is a great app for those who want to experience the classic walkie-talkie communication style. Its Baby Monitor mode is also a useful feature for parents. However, it may not be suitable for professional or business communication needs.