Cotabby is a free, AGPL-3.0 open-source macOS app that adds passive inline AI autocomplete to any text field - ghost text appears as you type, Tab to accept, no account or subscription required. It supports Apple Intelligence (macOS 26+), local GGUF models via llama.cpp, and OpenAI-compatible endpoints. Its main limits: macOS only (no Windows or Linux), no voice dictation, no active AI command layer, no meeting transcription, and beta-quality polish (v0.0.4-beta as of August 2026) with no commercial support channel. If any of those are the constraint, here are the best alternatives - ranked with honest pros and cons.