Comparison

PureMarkdown vs Lumen

Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.

Head to head
About

PureMarkdown

Features
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Features: 1.Cross-device Sync Sync across iPhone / iPad / Mac with no device limits and real-time updates 2.Privacy & Security Notes are stored only in your iCloud. No external servers or background data collection 3.Efficient Writing Support for note templates and custom templates for quick creation; keyboard shortcuts available on Mac 4.Multiple Export Formats Export notes as images, PDFs, or mind maps for easy sharing, archiving, and structuring 5.Data Migration Batch import and export of Markdown notes for easy backup and migration 6.Organization Manage notes with notebooks and tags to keep your content well-structured If you are looking for a simple, privacy-focused note-taking app that works seamlessly across devices, PureMarkdown is a great choice. This app does not collect user data. All content is stored only in the user’s iCloud account.

About

Lumen

This app acts as a browser that remembers what you read, building a personal knowledge base from engaged pages. It allows you to ask questions in plain English about your reading history, with answers generated by an on-device AI. All your data remains private and offline.

Highlights
  • On-device AI knowledge base
  • Plain English questioning
  • Automatic content organization
  • Private and offline browsing
  • Tracker blocking
  • Source citation for answers
Read full description

Lumen is a browser with a memory. Most browsers forget the second you close a tab. Lumen does not. As you read, it quietly builds a personal knowledge base from the pages you actually engage with, and then lets you ask questions about any of it in plain English, answered by an AI model that runs entirely on your device. Nothing you read, nothing you ask, and nothing Lumen learns about you ever leaves your phone. WHAT IT DOES Lumen reads along with you. It distinguishes between pages you genuinely read and pages you opened and swiped away, and it extracts the meaningful content from the ones that stuck. That content gets summarized, embedded, and organized into a searchable knowledge base, all on-device. Later, when you want to find something, you do not have to dig through history or remember which tab it was in. You just ask: "What did I read about sourdough starters last week?" "Summarize that article about the new M-series chips." "What were the main arguments in that piece I read on Tuesday?" Every answer cites the pages it came from, so you can jump straight back to the source. AUTO-ORGANIZED Your reading sorts itself into a clean hierarchy: Topics, Websites, and Pages. Each level carries its own AI-generated summary, so you can scan what you have been learning at a glance. No tagging, no folders to maintain. Lumen handles it in the background. PRIVATE BY DEFAULT Lumen has no server. There is quite literally nothing to send. On-device LLM: a quantized Llama 3.2 model runs locally through Apple's MLX framework. Local SQLite storage: your reading history, summaries, and embeddings never leave the device. Built-in privacy: tracker blocking, third-party cookie blocking, and fingerprint resistance. Secure: HTTPS-only by default, with mixed-content blocking. No strings attached: no accounts, no sync, no telemetry, no ads. The AI weights download once on first launch (~700 MB). After that, everything works fully offline: browsing, reading, asking, answering. BUILT FOR iOS Lumen is written from scratch in Swift and SwiftUI, designed specifically for iPhone and iPad. It uses Apple's own frameworks wherever it can: NLEmbedding for semantic search, WKWebView for browsing, SQLite with FTS5 for full-text queries, and MLX Swift for on-device inference. Zero third-party trackers. Zero external services. WHO IT'S FOR While most browsers treat the web as a feed to scroll past, Lumen treats it as a library worth keeping. If you read a lot online and constantly think "I know I saw something about this recently but I cannot find it again," Lumen is for you. Researchers, students, writers, developers, and lifelong learners. You do not need to change how you browse. Browse normally, and Lumen takes care of the rest. REQUIREMENTS iOS 18 or later. iPhone with Apple Silicon recommended for the fastest on-device AI performance.

Screenshots

PureMarkdown4 screens
Lumen4 screens

Verdict

The call

The clearest difference is device support: PureMarkdown at 3 against Lumen's 1. On price, update cadence, ads and in-app purchases 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

CostPrice · In-app purchases · Ads · Monetization

Both are free to download. Neither carries in-app purchases, so what you see is what you pay.

UpkeepUpdate frequency

Both ship on a similar rhythm, roughly every 2 weeks. The most recent releases landed on September 19, 2026 and June 28, 2026 respectively.

Scorecard1 real difference · 9 level
PureMarkdown versus Lumen: the parameters behind the verdict, then further details
ParameterPureMarkdownLumen
PriceFreeFree
Rating—5.0 (4 ratings) — better
Positive reviews—100.0% of reviews
Number of ratings—4 — better
Update frequencyEvery 2 weeksEvery 2 weeks
AdsNoNo
In-app purchasesNoNo
Monetization—Free
DevicesiPhone, iPad, Mac — betteriPhone
Requires iOS17.6 — better18.0
Further details — not scored
Size3 MB28 MB
Age rating4+17+
Developerzeyang huangDaniel Kosukhin

In-app purchases

None

PureMarkdown

No in-app purchases

None

Lumen

No in-app purchases

Questions

Is PureMarkdown free?
PureMarkdown is free to download, with no in-app purchases.
Is Lumen free?
Lumen is free to download, with no in-app purchases.
Do PureMarkdown or Lumen have ads?
Neither PureMarkdown nor Lumen shows ads.
Which is updated more often, PureMarkdown or Lumen?
PureMarkdown ships an update every 2 weeks, and Lumen every 2 weeks. Most recently, PureMarkdown was updated on September 19, 2026 and Lumen on June 28, 2026.

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