rikkahub/rikkahub

RikkaHub is an Android app for chatting with AI language models. Rather than locking you into one provider, it lets you connect to different AI services by entering your own API key and server address. It works with any API that follows the formats used by OpenAI, Google, or Anthropic, which covers a wide range of AI services. The app supports sending text, images, PDFs, and Word documents in a conversation. It renders responses with code highlighting, math formulas, tables, and diagrams using a format called Mermaid. There is a message branching feature, which means you can fork a conversation at any point to try different directions. The app also supports web search through several different search providers and includes an AI translation feature. Other features listed in the README include memory (similar to how ChatGPT remembers things about you across conversations), custom AI agents you can configure yourself, the ability to import character cards from a platform called Silly Tavern, and QR code-based import and export for sharing your provider settings. There is also support for a standard called MCP, which is a protocol for AI tools to call external services. The interface uses Android's Material You design system, which means the app's colors adapt to your phone's wallpaper, and it supports dark mode. It is built with Kotlin and Jetpack Compose. The app is available on Google Play and through the project's own website. The maintainer notes that pull requests for new features, translations, or large AI-generated refactors will be rejected, as the project follows a specific vision.