Turn a Textbook Page into Flashcards with Your iPhone

The textbook is the last thing in a student's life that has not been digitised, and it is the thing most often being studied. Typing a page of it into a flashcard app takes twenty minutes and produces cards you resent. The phone in your pocket can read the page instead.

This is the workflow, written for whichever app you use. The mechanics differ; the judgement calls do not.

Photograph one page, not the chapter

The single biggest quality lever is scope. A photograph of one page produces cards about one idea. A stack of fifteen photographs produces a generic summary of a chapter, because no model can hold that much context and stay specific.

Work in sections. If a section runs across a page turn, photograph both pages and treat them as one capture. If a page holds three unrelated topics, capture it three times and crop to one each.

Get the photograph right the first time

Text recognition on a phone is very good, and it still fails on the same four things:

• Curved pages. A spine that curves away bends the lines of text. Press the book flat, or photograph one page at a time with the book fully open.
• Shadow from your own hand. Light from behind you, phone directly overhead. A window is better than a ceiling lamp.
• Angle. Square the camera to the page. A trapezoid page confuses line ordering, so columns merge into each other.
• Highlighter. Heavy yellow or pink over text reduces contrast enough to lose words. Photograph before you highlight, or use a lighter hand.

Two-column layouts — most medical and science textbooks — are the case where the angle matters most. If the columns are being read across rather than down, you will see it immediately in the extracted text, which is why the next step exists.

Read what it read, before you generate

Every good capture flow shows you the extracted text before it writes anything. Do not skip that screen. Thirty seconds there prevents a whole deck of cards built on a misread word.

What to look for:

• Names and numbers. These are what text recognition gets wrong and what flashcards are most often about. "Angiotensin" and "angiotensinogen" are one letter apart and one is the substrate of the other.
• Units and subscripts. "CO2" and "CO₂" are fine; "C02" with a zero is not.
• Merged columns. A sentence that changes subject mid-clause is usually two columns read across.
• Figure captions. They are often picked up and often useless in the middle of prose. Delete them, or capture the figure separately if the figure is the point.

Then trim. Cut the paragraph of context you already know, the worked example you have done, and the chapter summary that repeats what you just captured. The narrower the source, the better the cards.

Let the cards carry their source

The most useful property a generated card can have is the sentence it came from. When a card looks wrong at 11pm the week before an exam — and one will — the difference between checking it in two seconds and losing faith in the whole deck is whether the source is attached to the card.

If your tool offers it, turn it on. If it does not, put the page number in the deck name. You will use it.

Quiz first, then keep what you missed

Here is the step almost nobody does, and it is the one that makes the difference.

After generating, do not review the cards. Take a short quiz on them instead — five questions is enough. Then keep only the cards for the questions you got wrong, and throw the rest away.

The reasoning is boring and well established: reviewing material you already know feels productive and teaches you nothing. A deck of sixty cards from a page you mostly understood is fifty cards of busywork wrapped around the ten that matter. Cutting it before you start reviewing is the whole trick, and it is much easier to do on the day you made the cards than three weeks later.

If your tool does not quiz first, do it by hand: run through the new cards once, delete every one you answered instantly, and start the real reviews tomorrow with what is left.

Then stop making cards for the day

Capture is addictive in a way that review is not. Photographing pages feels like studying and takes no effort, which is exactly the problem — a 400-card backlog you will never clear is worse than the 40 cards you would have reviewed.

A practical ceiling: make cards from what you actually read today, and no more. Most daily free tiers, Klarrity's included at five generations a day, land near that number for a reason.

Doing this in Klarrity for iPhone

The workflow above is the general one. Concretely, in Klarrity for iPhone:

1. Point the camera at the page and take the photograph. A PDF works the same way, from the Files app.
2. The app shows you the text it read, editable, before anything is generated. Fix names, cut what you know.
3. It quizzes you on five questions, then keeps flashcards only for what you missed. The free tier runs one of these rounds a day; on Pro there is no limit.
4. Each card keeps its source sentence, one tap away.
5. Give it your exam date and it prints one number for how ready you are for it, built from what you have got right rather than from how many cards you own.

There is no account and no sign-in, review works offline, and the deck exports as an Anki .apkg on the free tier, so the cards are yours to take elsewhere. Free every day: five generations a day, one quiz-first round a day, unlimited review, four starter decks, no ads. Pro is $6.99 a month or $39.99 a year, with no free trial.

If the page you want is on a screen rather than in a book, the Chrome extension does the same job from an open tab.

Frequently Asked Questions

How many textbook pages should I photograph at once?

One page, or one section that runs across a page turn. A stack of pages produces a generic chapter summary rather than specific cards, because no model stays precise across that much text.

Does it work on a two-column textbook?

Usually, but two columns are the case most likely to be read across instead of down. Check the extracted text before generating — a sentence that changes subject mid-clause is the sign.

Can I do this with a PDF instead of a photo?

Yes, and the text will be cleaner because there is no recognition step. The same judgement applies: one section at a time, and trim what you already know.

Why quiz before reviewing?

Because reviewing cards you already know feels productive and teaches nothing. Quizzing first tells you which of the new cards are worth keeping, and it is far easier to cut them on the day you made them.

Can I get the cards into Anki?

In Klarrity, yes, on the free tier: every deck exports as an Anki .apkg you can open on any platform. If you use a different tool, check that it names an export format before you build a term's worth of cards in it.