Liner Alternative — Build Your Own AI Highlighter
Liner is a strong product, especially for the integrated mobile experience. If you primarily work in Chrome and want to avoid recurring subscription costs while keeping your data in your own stack, PlugThis lets you build a similar workflow.
About Liner
Liner is a Chrome extension that combines web highlighting with AI-powered search and summarization. It highlights text on webpages, saves them to a personal library, and uses AI to summarize content and answer questions about saved highlights.
Pricing: Liner is freemium with limited free usage. Paid plans include Liner Pro at around $12.83/month for unlimited highlights and AI features.
Audience: Researchers, students, and professionals who do deep reading across many sources and want AI assistance.
PlugThis vs Liner
| Feature | PlugThis | Liner |
|---|---|---|
| Pricing | $89 one-time | ~$12.83/month for Pro |
| Free tier | Yes — try before paying | Yes — limited |
| AI provider | Bring your own keys | Liner-managed |
| Highlighting | Built into your extension | Built-in |
| AI search across highlights | Build it (Supabase + embeddings) | Built-in |
| Mobile app | No (Chrome extension only) | Yes |
| Source code | Full source | Closed |
| Privacy | Your data stays in your stack | Liner's servers |
What Liner does well
- Tight integration of highlighting + AI search
- Polished mobile and web app companions
- Good free tier for trying the product
- Active development with frequent updates
Build it yourself with PlugThis
Build time: About 15 minutes (Supabase setup adds time)
What you get:
- AI semantic search across all your highlights using vector embeddings
- RAG pattern — ask questions, get answers grounded in your saved highlights
- Bring your own OpenAI keys — no AI usage caps beyond your spend
- Data lives in your Supabase project — full ownership and exportability
- Customizable: add tags, categories, or any other field your workflow needs
- Lifetime ownership, no subscription
Build a Chrome extension called "Smart Highlighter Pro" combining highlighting with AI features. The extension should: (1) let users highlight text on any webpage by selecting it and clicking a floating button, (2) save highlights to a Supabase backend (set up automatically) with: text, URL, title, timestamp, surrounding context, embedding vector (generated via OpenAI embeddings API), (3) provide a popup with: list of recent highlights, search box that semantically searches across all saved highlights using embeddings, "Ask AI" button that lets the user ask questions answered using their highlight library as context (RAG pattern), (4) include an options page for OpenAI API key entry. Permissions: storage, activeTab. Host permissions: <all_urls>, https://api.openai.com/*. Manifest V3 with Supabase backend.
Pricing comparison
Liner
$12.83/month for Liner Pro
PlugThis
$89 one-time + ~$5/month OpenAI usage + Supabase free tier
PlugThis breaks even vs Liner Pro in 7 months. After that, you save ~$95/year ongoing.
Other alternatives to explore
Glasp alternative
Glasp alternative — build your own web highlighter Chrome extension with PlugThis. Private highlights, AI summaries, $89 lifetime.
Remio alternative
Remio alternative — build your own AI research and knowledge management Chrome extension with PlugThis. $89 lifetime, full ownership.
Notion Web Clipper alternative
Notion Web Clipper alternative — build your own clipping extension with AI summary, auto-tagging, and full content. PlugThis, $89 lifetime.
Eightify alternative
Eightify alternative — build your own AI YouTube summarizer Chrome extension with PlugThis. $89 lifetime, your own API keys, full code.
Build your own Liner alternative now.
Paste the prompt above into PlugThis and ship your custom version in minutes.
Disclosure: PlugThis is a competing product to Liner. This comparison is intended for users actively evaluating both options. We last verified the Liner information on this page on 2026-05-14. Pricing and features may have changed since — please check the Liner website for current details.
Liner alternative — FAQ
Will my highlight search be as good as Liner's?
Semantic search using OpenAI embeddings is comparable in quality to most commercial implementations. Liner has had time to refine ranking, but for personal libraries (hundreds to thousands of highlights), the difference is minimal.
Do I need to know Supabase to build this?
No. PlugThis sets up Supabase tables, auth, and API integration automatically when you describe an extension that needs persistent data.
Can I have a mobile companion app like Liner?
Not via PlugThis directly — PlugThis builds Chrome extensions, not mobile apps. But because your data lives in your Supabase project, building a mobile app later (or using a no-code tool like Glide) is straightforward.