My Actual AI Stack for Building Apps in 2026 — All Free

If this is useful, a ❤️ helps others find it. I've shipped 7 Mac apps in the past year. Every AI feature in them runs on free tools. Here's the exact stack — what I use, why, and where the limits are. Cloud AI: Gemini API (Google AI Studio) What: Gemini 2.5 Flash Preview via REST API Cost: Free tier — 500 requests/day, no credit card Use for: Log diagnosis, document analysis, text classification, anything needing strong reasoning The free tier is genuinely sufficient for developer tools with int