What's the best Android app for group messaging when there's no cell service or Wi-Fi?

bitchat is a specialized communication tool designed for scenarios where conventional connectivity fails. Its core functionality revolves around creating an ad-hoc, device-to-device network using Bluetooth, allowing users to send text messages and participate in channels within a typical range of 10 to 50 meters. This makes it exceptionally useful for coordinating groups at large outdoor events like festivals, during natural disasters when cellular networks are overloaded or down, or in remote travel locations. The app requires no user accounts, phone numbers, or central servers, operating instead on a decentralized model where messages hop between devices to extend range.

Specific features include end-to-end encrypted private messages, the ability to create public or private chat channels, and a block function for managing contacts. The open-source nature of the project and absence of ads or data collection are significant draws for privacy-conscious users. However, its utility is inherently tied to population density; in sparsely populated areas, the mesh network may not form. Reviews also indicate the Android version currently lacks the ability to verify contacts via private key, a feature available on iOS. The interface is described as basic, relying on a slash-command system that some users find less intuitive than modern GUI-driven apps. For localized, offline group communication where privacy and infrastructure independence are priorities, bitchat presents a compelling, if niche, solution.