ReplyKit

ReplyKit is a Chrome extension and mobile web app for drafting replies to posts on X, LinkedIn, and Reddit. It is built for people who want to answer posts without writing the reply from scratch, and it presents itself as a way to keep up with frequent replying across those three platforms.

The extension works in Chrome and other Chromium browsers. The basic flow is to install it, open a post, click generate, and get a draft reply. ReplyKit says it picks a tone and produces a reply that answers the post rather than a generic response. It also adjusts length, formality, and what counts as witty on each platform, and it reads the parent thread for context. The product offers eight tones: thoughtful, witty, informative, support, analyze, question, challenging, and humorous. It also lets users set background and interests so replies sound more like them. For Reddit, it shows a warning about AI content and tunes drafts to sound human-like. On mobile, it runs as a web app; on Android, posts can also be shared into it from X, LinkedIn, or Reddit.

Pricing is split into a free tier and a Pro plan. The free tier costs €0 and includes 5 AI replies per day, brings your own API key, and works with OpenAI, Claude, or Gemini. Pro costs €6.99 per month, allows 1,000 AI replies per month, does not require an API key, and includes those providers. The page also states that no account is required and that the extension runs in the browser. ReplyKit describes its own behavior as suggesting text only, without auto-posting or using platform logins.