A "voice app" is an application that utilizes voice as a primary input interface, allowing users to interact with it solely through voice commands. The term lacks a universally accepted definition, but its average guess is that of a mobile app with optional voice commands. Voice is not a platform shift, but rather an interface shift, and mobile will likely remain the largest platform for voice interface use in the present and near future. However, omni-channel voice assistants have the potential to become the dominant platform. The opportunity for voice app startups lies in great conversation design and leveraging unique functionalities of being a voice app living on a voice assistant. Visuals can change everything, enabling faster input speed and better user experiences. As voice interfaces grow in prominence, we'll see the rise of multi-interface apps that provide superior user-experience flexibility. The future will bring proactive operating systems with true conversational AI capabilities, allowing companies to carry consistent conversations across channels.