Tweetback is an AI copilot for X (formerly Twitter) that integrates as a browser extension to generate editable AI-powered replies and posts (text and images), train custom writing styles from real accounts, and automate targeted replies via keyword-based Auto Reply and Watchlists; it runs with your own API key (OpenAI, Gemini, Claude, Grok, OpenRouter or local models) so you control cost, privacy, and model choice while staying in-context on X, making it easy for creators, marketers, and founders to scale consistent, on-voice engagement that drives visibility and monetization.