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Space Play / Pause
← → Step backward / forward
↑ ↓ Adjust word stream speed
Hold Shift Slow the word stream while held, back to your speed on release
Ctrl / ⌘ F Search this document
E Show the equation when an equation marker is on screen
Read Aloud narrates the text while keeping the word stream synchronized. Voice speed and visual word-stream speed are controlled separately.
The voice pauses briefly after each heading in the Contents, so a section title does not run straight into the text beneath it.
Pausing opens the word stream out into the whole sentence, so you can look back at a word you missed. Tap any word in it to carry on from there.
The word stream takes the whole screen. Contents, above the controls, opens the side panel from the bottom — Contents, Search, Figures, Text and References — and choosing a section closes it again so you can see the stream move. Tap the dimmed stream or pull the handle to close it without choosing.
The controls keep play and speed on screen. More opens the rest: Stop, the voice, the reading face and size, Skip and Pacing. Open a file, the Library, Paste text, Help and dark mode are in the menu at the top right.
In Study, the switch at the top moves between the Outline, the Section you are studying and its Tools — the coach, practice, notes and figures. Picking a section in the outline opens it.
On a small screen the word stream caps its type size so long words fit; your chosen size still applies on a larger screen.
The first menu under Display sets the reading face, used for the word stream and the Text tab. Serif is the default. Sans has plainer letterforms that some readers find quicker to take in at speed. Hyperlegible is Atkinson Hyperlegible, designed so that easily confused characters such as I, l and 1 or b and d stay distinct; it can help with low vision or when words pass quickly.
The second menu sets the size of the word stream. The face applies to every document; the size is remembered for each document.
Section estimates the time remaining in the current section. Full-Text estimates the time remaining in the entire loaded file.
Pacing varies how long each word stays on screen according to how common that word is. Ordinary words like the and was pass quickly; unfamiliar and technical words are held longer, so a term you are meeting for the first time gets the extra moment it needs instead of going by at the same rate as everything else.
There are three settings. Even gives every word the same length of time. Subtle, the default, applies about half the variation. Natural applies it in full, where the longest-held words stay on screen roughly three times as long as the shortest.
Whichever you pick, the words-per-minute you set does not change. The time is redistributed between words rather than added to them, so a document takes the same length of time to read at every setting — only the rhythm differs.
Pacing takes account of the document itself, not only general English. A term that runs throughout a paper counts as part of that paper's vocabulary, so words particular to your field pass at full speed rather than being held as though they were unfamiliar.
The word stream also holds a little longer on the last word of each heading in the Contents, marking where a new section begins without adding punctuation to the text.
The brief pauses at sentence and clause endings are separate from this and stay active at every setting, including Even. Pacing applies to silent reading only; Read Aloud follows the voice's own timing.
A displayed equation cannot be read as words, so Gwion takes it out of the text and leaves a marker where it stood: [Equation 12] when the paper numbers it, [equation] when it does not. The sentence around it reads on as one sentence, and the voice says “Equation 12” as it passes.
To see the equation itself, tap an underlined marker in the Text tab, click the marker in the word stream, or press E while it is on screen. The equation opens enlarged, cut from the page, with Go to text to return to where you were. A marker that is not underlined has no picture to show — usually a fragment of symbols rather than a full displayed equation.
If the word stream or the voice is playing, it pauses while a figure or equation is open full size and carries on from the same word when you close it. Go to text moves you instead, so playback stays paused there until you press play. Looking through the Figures or Equations panel without opening anything never pauses.
Program listings are handled the same way. A block of code is taken out as a whole and marked [code]; tap it to see the listing as printed, captioned with its page.
Markers stay visible when [ ] is ticked under Skip. That setting hides bracketed citations, not equations. Every equation in the document is also listed in the Equations panel.
The Search tab finds any text in the open document. Results are grouped by section, and clicking a result jumps the word stream to that point without losing your place. Search matches partial words, so "ion" also finds "solution". Press Ctrl / ⌘ F from anywhere to jump straight to it.
Use Contents and Text to move around the document. Clicking text or a contents item updates the word stream position.
Select any passage in the Text tab and a small toolbar appears. Save to Notes keeps it as a highlight, tagged with the section it came from and the point in the document where it sits, so it appears in Notes and in the Study panel's saved items and stays findable later.
The other button on that toolbar, Split here, starts a new paragraph immediately before your selection. Use it where extraction has run two things together — a heading absorbed into the paragraph beneath it, or two sections joined across a page break. Splitting affects the reading stream, so the pieces can then be moved or removed independently in Arrange.
Make heading, on the same toolbar, turns the selected words into a heading. It appears in Contents at that point in the document and starts a new section, so Study treats what follows as its own section too.
Use it where a document's own structure did not come through: a paper with no table of contents and no detected headings, or one where only some sections were found. Selecting part of a paragraph splits it, so the heading is the words you chose rather than the whole paragraph.
Selecting inside any heading changes the button to Remove heading. It leaves the Contents and the text reads on as body. This works on headings Gwion detected as well as ones you made — useful where a displayed equation, a caption or a stray line has been taken for a heading.
Arrange, at the top of the Text tab, turns the text into blocks you can reorder. Hovering a paragraph shows arrows to move it up or down and a cross to take it out of the reading stream. Removed paragraphs are not deleted — they stay in place marked removed, greyed out, with a Restore button, and they are skipped by narration and by the word stream.
This is for fixing what extraction got wrong on a particular document: a running header spliced into a sentence, a caption landing mid-paragraph, a footnote interrupting the prose. Undo steps back one edit at a time and Revert restores the original extracted order.
Your edits are saved per document and are anchored to the text itself rather than to positions, so they survive re-extraction — including a Rebuild — and are still there when you reopen the document.
Study mode is a three-part workspace. The left panel navigates and tracks progress, the center panel presents the document as study material, and the right panel holds your tools.
Left navigates by Outline, Concepts, Key Points, or Saved items. Center shows the document as Key Points, a Simplified rewrite, or a Concept Map. Right holds the Study Coach, Quick Tools, and tabs for Notes, Practice, and Figures.
The center panel's select bar — Explain, Simplify, Quiz This, Flashcard, Save Highlight — stays disabled until you select text, then acts on that selection.
The right panel's Quick Tools — Explain, Simplify, Memory Anchor — use your selection if you have one, and otherwise fall back to the current section. Quiz Section always uses the current section.
The Practice tab generates a quiz or flashcards for what you're studying, drawing on the section's figures as well as its text, and Figures shows figures related to your position. Add to Review Sheet saves the current material to revisit later in Notes.
Quizzes and flashcards are for self-checking. After revealing an answer or flipping a card, tap Got it or Missed it: Gwion does not grade you, so those taps are what the coach learns from. Skipping them is fine.
Explain It Back (Practice) asks you to write what a section argues, in your own words, and marks it against the section's key points: each one covered, partly covered, missing or contradicted, with the words of yours that earned the mark and, where it falls short, what the text says. Your first explanation of a section each day counts toward its review, like a quiz; one more attempt that day is practice and changes nothing. The coach suggests the best day for the next one.
Walk me through it (on the Concept Map tab) reads the map aloud one idea at a time, lighting each as the voice reaches it, and stops now and then to ask about an idea from a little earlier. Tap Show the answer, then Got it or Missed it: those count as a test for the section, like a quiz. It uses the voice and its minutes, not Study allowance.
Study Across Sections (Student and Pro) works on consecutive sections at once, up to 4 on Student and 10 on Pro: a quiz or flashcards with about two items from each section, mixed together, or one concept map of how their ideas connect. Mixed questions make you work out which idea each one is about, which is closer to how an exam tests you. Sections you have not studied yet are studied first and count as usual; combining them into the quiz, cards or map is included. Each answer updates the section its question came from.
The coach keeps track on its own. Reading a section in the word stream, Key Points, Simplified, a concept map and a memory anchor count as study and give a small boost. Got it / Missed it and quick checks count as tests, and only tests can mark a section as holding or bring its review forward. A section that has only been read shows as untested. When a section is due, the coach offers a three-question quick check. Log a study session is for studying done away from Gwion.
Notes → Retention shows every section you have studied, across all your documents: what is due today, and how each section has held up over the last two weeks.
To stop tracking something, use the ⋯ at the end of its row: a single section, such as a References heading picked up as a section, or a whole document once a course is over. Its estimate, history and saved check questions are cleared, and reading it again will not bring it back; quizzing or checking a section later starts tracking that section afresh. The document itself stays in your Library with its notes. Removing a document from the Library clears its tracking as well.
How you studied matters as much as how it felt. Recalling something without looking builds more durable memory than rereading it does, even though rereading feels more fluent at the time. So the same answers after a reading pass produce a shorter interval than after a quiz. Denser sections — more equations, more figures — also fade faster, so they come up for review sooner.
When other sections in the document have come up for review, the coach shows the first of them under Due, with a count if there are more. That is review order, not document order — a section due for review may be behind you as easily as ahead. Clicking it takes you there.
How much to trust it. The specific numbers are a rough guide, not a measurement — nothing here is calibrated against your results or anyone else's. Read the output as a comparison, not a reading: “this section is shakier than that one” is meaningful, “holds about a week” is a rough shape rather than a deadline. That is why Gwion says solid, settling, and fading rather than a percentage, and gives horizons in weeks and months rather than exact days.
The coach is a prompt to review, not a verdict on what you know. If it says a section is solid and you are not confident, trust yourself over it.
Some PDFs carry a text layer that is wrong rather than missing — a scan whose characters were guessed at, or a paper whose equations arrive as scrambled symbols. When Gwion can tell it is looking at a document like that, it offers to re-read the pages in the Equations panel.
You pick the pages, at the equations. Every equation in the Equations panel carries a Re-read page button. Pressing it selects that page rather than starting anything, so you can look through the crops, mark the ones whose text does not match the picture, and see the total before you commit. A bar at the foot of the panel shows how many pages you have chosen and roughly how long they will take; nothing is read until you press it.
One section at a time. Once you select a page, the buttons on pages outside that section dim — a page that reads badly usually means its neighbours do too. Clear the selection to choose somewhere else. This works on a document of any length.
Whole documents. When a document has almost no readable text at all — a scan with no usable text layer — every page needs re-reading, and Gwion offers that up front for documents of up to about forty pages. Every page re-read counts toward your plan’s monthly allowance; the account menu shows how many you have left.
What it does. Each page you picked is rendered as an image and read back as text, and its equations come back as real mathematics rather than loose symbols. That page's text then replaces what was there before, so the reading stream, the Text tab and narration all pick up the corrected version. Pages you did not pick are untouched.
What it costs, and how to undo it. Pages are read one at a time and you can watch the progress and stop part way; whatever finished is kept. Undo restores the original extraction — including anything you had highlighted or annotated on those pages — and undoes every re-read of the document, not only the most recent one.
It is a second opinion, not a correction. The result is one model's reading of a page image, and it can be wrong in its own ways: a symbol misread, a line dropped, a table flattened. The button sits on the crop so you can see what the equation actually looks like alongside what the text made of it. If a page comes back worse, Undo it.
Everything you save — notes, bookmarks, highlights, and the Review Sheet — collects here, filterable by type. Go To Source on any item jumps back to where it came from in the document. Highlights and notes are made while reading or studying; this is where they gather for review.
Retention shows every section you have studied, across all your documents. What is due today comes first; below it, each section's last two weeks and the week ahead. A hollow dot is study, a solid dot is a test, and stronger gold means a section is holding. Tap any day for details, or a section to open it.
Documents you open are saved on your device and listed on the start screen and in the Library tab, so you can reopen one without finding the file again. Your highlights, notes, reading position, and study history are stored on your device too, and return with the document. They live in this browser only: clearing browser data, a private window or a new device starts empty. Use Back up in the Library to save them to a file, and Restore to bring them back — on this browser or another. Reopening is instant because the parsed text is cached locally.
What leaves this browser. Four features need Gwion’s servers: finding the sections of a PDF that has no structure of its own, study tools, narration, and re-reading a page. Each sends only what it needs, and your library, notes, highlights and history never leave this browser. The Privacy Policy sets out exactly what is sent, where it is processed, and how long anything is kept. Because those features send text off your device, please don’t put confidential records or sensitive personal information through them.
Rebuild clears the cached text for every document while keeping the files themselves. Use it if a document looks wrong, and its text will be rebuilt the next time you open it.
PDF, DOCX, EPUB, ODT, TXT, Markdown, HTML, and image files are supported. RTF support is basic. Legacy .doc files should be saved as .docx first. Images and scanned PDFs use OCR when needed.
Gwion works best with structured documents, and looks for that structure in three places. If your file has a table of contents, that is used to split the text into real sections for reading and Study Mode. If it does not, Gwion reads any heading structure stored inside the file — usually present in exported documents, even when the headings are not visually larger than the body text. Failing both, documents are analyzed to recover their sections automatically. This works best on scientific papers; others are divided more coarsely.
Word pacing uses frequency data from the New General Service List and New Academic Word List (Browne, C., Culligan, B., & Phillips, J., 2013), available at newgeneralservicelist.com and used under a Creative Commons Attribution-ShareAlike 4.0 licence. Gwion groups the data into frequency bands; the values are otherwise unmodified. Development of the initial NGSL wordlist was made possible through approved access to the Cambridge English Corpus.
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