Early AF is market research and marketing guidance for solo app builders. Pick a realistic opportunity from dated evidence, understand who needs it, and show up in conversations worth answering yourself. You get a free reviewed daily idea, a research path from real complaints and workarounds to a first experiment, and Reply Radar: a Chrome extension that scores public Reddit (optional X) posts for audience fit and queues them for manual reply. Honest limits: no auto-reply, no DM blasts, not a full marketing suite.