WebRTC is an open-source technology that facilitates the development of voice and video chat applications, supporting peer-to-peer connectivity without the need for intermediary servers, which can significantly reduce bandwidth costs. It's ideal for creating Skype-like applications on web and mobile platforms, including iOS and Android, and is further simplified by the use of the PubNub WebRTC SDK. This SDK offers features such as high-replication signaling, call presence detection, and mobile push notifications, and is compatible with both Android and iOS devices. The SDK aims to make it easy for developers by providing simple methods for initiating and receiving calls, as well as offering additional features like multi-party calling and session management. A live demo and implementation reference showcase its capabilities, including photo transmission, JSON app messaging, and security features like SSL and AES256 encryption. WebRTC's broad applicability is demonstrated through various use cases, from traditional phone replacements to real-time communication solutions, making it a versatile option for developers looking to build robust communication apps.