PDF reader
Read, highlight, actually remember.
A PDF reader that connects to your study system. Highlight a passage and it becomes a flashcard — not a yellow stripe you never revisit.
Highlight → Card
Highlights that become flashcards.
The inner planets orbit faster because the Sun's gravity weakens with distance.
Why do inner planets orbit faster than outer ones?
p. 142What happens to the Sun's gravity as distance grows?
p. 142You highlight 40 pages of a textbook. You feel productive. Three weeks later you can't recall a single highlighted fact. The problem isn't your memory — it's that highlighting without practice is reading, not studying.
The workflow
From page to practice. No gap.
Other PDF readers stop at highlighting. Mento connects highlighting to your study loop — so the things you mark are the things you practice.
Upload or drop your PDF
Drag textbooks, papers, lecture slides, or supplements into Mento. They live alongside your notes — accessible from any device, always searchable.
Read and highlight
Read in a clean, focused viewer. Highlight key passages, add margin notes, and mark pages. Your annotations are saved and searchable across all your PDFs.
Extract to notes or cards
Select a highlight and send it to your notes as a structured excerpt, or trigger AI to generate flashcards directly from the passage. Source linking preserved automatically.
Study what you highlighted
Cards generated from PDFs enter your spaced repetition queue. Every card links back to the original page and highlight — tap through to re-read the context anytime.
Capabilities
A reader built for studying.
Not a generic document viewer. A PDF reader designed for one purpose: turning what you read into what you know.
Clean PDF viewer
Focused reading experience. Scroll, zoom, jump to pages. No clutter — just your text and your tools.
Highlights & notes
Color-coded highlights. Margin notes. Bookmarked pages. All annotations are searchable and exportable.
Highlight → Card
Select a highlight and generate flashcards with one click. AI reads the passage and produces recall-ready cards from your specific content.
Source linking
Every note and card extracted from a PDF links back to the exact page and highlight. Trace any fact back to its source in seconds.
Library management
All your PDFs in one library. Attach them to spaces and topics. Search across all documents and annotations simultaneously.
PDF → Study loop
The bridge no other app builds: from reading a PDF to practicing what it contains, without copy-pasting between three different tools.
Select → Define
Select a term, get a card that defines it.
For weeks at a time, Mars seems to reverse course — an effect called apparent retrograde motion that puzzled astronomers for centuries.
Definition
Apparent retrograde motion
The illusion that a planet drifts backward through the sky, created when Earth overtakes it in orbit.
p. 168From your selection
“Mars seems to reverse course — an effect called apparent retrograde motion.”
p. 168Highlights & notes
Mark up the page as you read.
Each planet moves on an ellipse with the Sun at one focus.
A planet sweeps out equal areas in equal times.
Note
Faster near the Sun, slower far away — ask about this in section.
2 highlights + 1 note — all searchable later
Source linking
Every card knows its page.
Astronomy · Review
Why do inner planets orbit faster than outer ones?
The Sun's gravity weakens with distance, so closer planets need more speed to stay in orbit.
The inner planets orbit faster because the Sun's gravity weakens with distance.
Every card traces back to its exact page and highlight
The gap nobody fills
Other readers stop at the highlight.
PDF readers give you highlighting. Flashcard apps give you SRS. But nobody connects the two. That gap — between the moment you encounter an idea and the moment you practice recalling it — is where most learning dies. Mento bridges it in one click.
Preview / Acrobat
Read + highlight
No study system
Anki / Quizlet
Flashcard SRS
No PDF reader
Mento
Read + highlight + cards + SRS
Complete loop
Highlight it. Study it. Keep it.
From PDF to flashcard in one click. No app-switching. Free to start.