Riff

Riff is built for people who comment and post on social networks for work. You click the wave button next to a post, paste a rough note, set three dials (how sharp, how salesy, how adventurous) and press Enter. Riff reads the post and its thread, or the whole DM conversation, and streams a draft into the panel for you to insert.

Highlights

• Replies and comments on X, LinkedIn, Facebook and Instagram, plus DMs on LinkedIn, Messenger and Instagram
• New posts from rough notes, with three suggested hooks and edits requested in plain words
• One-click rewrites: shorter, punchier, softer pitch, bolder, more human or ending with a question
• Repurpose turns a LinkedIn post into an X thread or an Instagram caption in that site's format
• Separate voices per brand, saved presets for repeat post types and per-site link handling
• Opens with Alt+Shift+R and works in Chrome on Windows, Mac, Linux and Chromebook Plus

Good to know

• Riff fills the reply or post box but never sends; publishing is always manual
• It relies on Gemini Nano built into Chrome, so the browser has to support that model on your device

Free to use, and aimed at founders, consultants and marketers who reply a lot and want their own point in every answer.