Comet vs Mark Bookmark
Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.
Comet
This AI-powered browser acts as a personal assistant, streamlining workflows and boosting focus. It offers unified AI search, instant context, and automation across websites for tasks like summarizing, shopping, and research. The assistant learns your habits to keep you organized and prevent lost tabs or inspiration.
- Unified AI search
- Instant context and automation
- Summarize, shop, schedule, research
- Personalized AI assistant
- Tab and inspiration organization
- Workflow streamlining
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Comet is an AI-powered browser that acts as a personal assistant and thinking partner. Boost your focus, streamline your workflow, and turn curiosity into momentum. · Unified AI search, instant context, and automation across every site. Summarize, shop, schedule, and research—directly in the browser. · Enjoy the web and let the AI assistant handle your chores · Do everything on your to-do list faster with Comet · Comet adapts to how you think and work, learning your habits to keep you organized. Never lose track of tabs or inspiration. Terms of Service: https://www.perplexity.ai/tos Privacy Policy: https://www.perplexity.ai/privacy
Mark Bookmark
Capture physical notes and ideas from books and printouts, turning them into organized insights. Automatically catalog your reading and search for specific passages. Chat with your highlights to trace ideas across different sources.
- Scan and save passages with high accuracy
- Record voice notes without unlocking device
- Automatic cataloging by book ISBN
- Searchable library of captured content
- AI chat with highlights and annotations
- Integrations with Notion and Readwise
- Offline capture and sync
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Mark II is a smart bookmark that captures your physical notes and ideas, and turns it into organized insights for you to revisit later CAPTURE WITHOUT LEAVING THE PAGE Scan a passage and it's saved, at 99% text accuracy, with any missing letters or words reconstructed automatically. Or hold to record a voice note instead. No unlocking your phone, no typing, no losing the thread of the chapter. It works across your whole reading life — hardcovers, paperbacks, printouts, research papers, Kindle, iPad, and handwriting (beta). 30+ languages. A LIBRARY THAT BUILDS ITSELF Scan a book's ISBN once (beta) and everything you capture from then on files itself under the right title. No folders to design, no tags to maintain, nothing named twice. Over months, it becomes a catalogue of what you've actually read — not a system you have to keep feeding. FIND THE QUOTE YOU HALF-REMEMBER Search for a fragment and get the passage back with its source. Filter by topic, theme, or the moment you captured it. Copy it straight into whatever you're writing. TALK TO WHAT YOU'VE READ Chat with your own highlights and annotations. Trace an idea across different books. Ask about the thing you know you read but can't place. Mark AI answers from what you've captured and nothing else — it won't invent a passage, and it won't summarize a book you never opened. FITS THE SYSTEM YOU ALREADY HAVE Integrations with Readwise, Notion, and many more apps to come. Mark isn't asking you to move in. It's asking you to feed what you've already built. WORKS WHEREVER YOU READ Bluetooth only — pairs like AirPods. Captures save on the device when you're out of range and sync the moment you're back. A single USB-C charge lasts about a week of heavy reading. YOUR NOTES, HELD CAREFULLY Highlights and voice notes are encrypted and stored on AWS in North America. We don't hold personally identifiable information alongside your library, and you can request deletion of your data at any time. WHO IT'S FOR Students who annotate. Researchers who cite. Readers who underline in pencil and mean it. Anyone who has closed a book and been unable to say what was in it. WHAT'S FREE Downloading Mark is free, and so is everything core: highlighting, audio capture, auto-organization, and basic AI chat. An optional subscription unlocks the heavier AI features and advanced integrations. REQUIREMENTS The Mark II device is required for scanning and voice capture. Each device pairs to one account at a time. iOS only. Support: Support@mark.engineering Privacy Policy: thinkwithmark.com/policies/privacy-policy
Screenshots
Verdict
The clearest difference is in-app purchases: Mark Bookmark at none against Comet's 3. Mark Bookmark also leads on review sentiment (100% vs 65%) and rating (5.0 vs 4.7). Comet's advantage is ratings volume (7.8K vs 2). On price, ads, device support and iOS requirement there is nothing between them.
Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS
Both are free to download. Comet sells 3 in-app purchases, starting at $20.00 per month. Mark Bookmark asks for nothing beyond the download.
Mark Bookmark holds the better App Store score, 5.0 against 4.7. That said, the two scores are not equally well evidenced: Comet has 7.8K ratings behind it against 2, so its average is the more settled of the two. Written reviews point the same way: 65% of Comet's written reviews are positive against 100% of Mark Bookmark's.
Comet ships an update weekly, Mark Bookmark every 4 days. The most recent releases landed on October 26, 2026 and October 25, 2026 respectively.
| Parameter | Comet | Mark Bookmark |
|---|---|---|
| Price | Free | Free |
| Rating | 4.7 (7.8K ratings) | 5.0 (2 ratings) — better |
| Positive reviews | 65.2% of reviews | 100.0% of reviews — better |
| Number of ratings | 7.8K — better | 2 |
| Update frequency | Weekly | Every 4 days — better |
| Ads | No | No |
| In-app purchases | Yes | No — better |
| Monetization | Free with in-app purchases | Free — better |
| Devices | iPhone, iPad — better | iPhone |
| Requires iOS | 18.0 | 17.0 — better |
| Further details — not scored | ||
| Size | 285 MB | 121 MB |
| Age rating | 17+ | 4+ |
| Developer | Perplexity AI, Inc. | Mark Inc |
Customer experience
Comet
Mark Bookmark
In-app purchases
Comet
- Perplexity Pro$20.001 Month
- Perplexity Pro$200.001 Year
- Perplexity Max$200.001 Month
Mark Bookmark
No in-app purchases








