Lumlu
Drop in any PDF
Open a textbook, paper, or lecture slides straight from the share sheet. Read it your way, highlight what matters, and listen with read-aloud.
Lumlu Reader
The best way to learn dense PDFs.
Lumlu turns dense PDFs into flashcards and notes pulled straight from the page, then brings each one back exactly when you're about to forget. Free forever, offline. Premium adds Sync · AI.
Free to start. Reader, notes, and spaced repetition work fully offline — no account needed.
App Store — soonGoogle Play — soon
Coming soon to the App Store and Google Play.
Why it works
Spaced repetition that works
On-device FSRS schedules each review just before you'd forget.
Source-anchored
Every card cites the exact page it came from.
Works offline
Free tier, no account — reader, cards, and study run with no signal.
Any subject, any language
Generation auto-detects the PDF's language.
Spaced repetition powered by the open-source FSRS algorithm.
How it works
From a page you're staring at to a card you'll remember.
Three steps from a dense PDF to something you'll remember.
Capture flashcards & notes
Pick cards, key terms, a summary, or an explanation — grounded in your PDF.
Review until it sticks
Spaced repetition brings each card back right before you'd forget it. Rate Again, Hard, Good, or Easy, and the schedule adapts — weak spots get extra attention.
Features
When the card goes fuzzy, the page is still there.
The loop is simple. What holds is how study material stays tied to the page you were reading — and a reader built for learning, not just flipping.
Back to the page
Flashcards that quote the page they came from.
Lumlu writes flashcards, key terms, summaries, and explanations from exact quotes — and treats your highlights and notes the same. Every card and note anchors to its page and passage. When a detail slips, one tap puts you back on the source.
Exact quotesPage anchorsBack to source
Read your way
A reader built for learning, not just viewing.
Scroll or turn pages, Day or Night. Select any passage and the toolbar is there: highlight, note, make a card, or send it to AI study. When your eyes are done, read-aloud continues word by word — at your own pace.
Selection toolbarHighlights & notesRead-aloud
See it in action
Watch a page become a memory.
Real screens from Lumlu: read any PDF, highlight what matters, capture key passages, see your study hub, and review with spaced repetition.
Your libraryContinue reading or listen hands-free 
Read any PDFZoom and pan through dense pages 
Select a passageHighlight, note, card — or study with AI 
Highlight as you goMark what matters with color and notes 
Your study hubAll cards and notes from the document 
Review when it countsSpaced repetition brings cards back before you forget
Free for everyone
Send study sets to a classmate — not a marketplace.
Share flashcards and notes from your PDFs with a file package or an anyone-with-the-link Share link. Recipients import into Lumlu and study offline. The PDF is never uploaded with a link; progress stays private.
Handoff is free. Premium is Sync and a higher daily AI allowance — not “can share.”
A study shelf in Lumlu — a set like this is what a handoff packages: cards and notes, with the PDF only in a local file package.
Desktop apps
Native apps for Mac, Windows, and Linux. Downloads coming soon.
Study on your desktop
The same reading and study experience, built for your computer. Premium subscription managed through Stripe — sync automatically when you're signed in.
macOS
Windows
Linux
Selection menu 
Highlights 
Review session 
Study hub
Downloads coming soon
Plans
Free, and genuinely useful. Premium when you want more.
The core experience is yours for free — Premium adds a higher daily AI allowance and Sync across devices.
Free
Everything you need to read and study, offline.
- Full PDF reader — highlights, ink, page notes, read-aloud
- Your own flashcards and notes
- Spaced repetition that works fully offline
- Send or receive study sets by file or link — free for everyone
- AI credits to try generation: 5 on device, 10 more when you sign in, plus 5 monthly
Works fully offline, start to finish.
Premium
Sync · AI
Everything in Free, plus:
- Higher daily AI allowance — around 30 generations per day
- Cloud backup and sync across your devices
$3.99/month or $35.99/year. 7-day free trial of Premium (monthly).
Prices shown in USD. Premium is one subscription — monthly or yearly.
Coming to the stores
Your free study app is almost here.
Offline reader, cards, and spaced repetition — free, no account needed. Premium is Sync and a higher daily AI allowance only if you want them.
App Store — soonGoogle Play — soon
Coming soon to the App Store and Google Play.
Free to start. Works offline. No account needed.