A reading companion for parents & kids

Every unfamiliar word,
a moment to grow.

BookWords turns hard-to-read words into flashcards that build vocabulary for early readers.

Try the prototype Read the story
Now in private beta on TestFlight
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B
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craning
KRAY-ning · verb
craning
KRAY-ning · verb
Definition
Stretching your neck to see something better.
For your kid
Reaching your head out to get a better look — like a tall crane bird.
From the book
"She was craning her neck over the garden fence."
Synonyms
stretching · peering · straining
The goal

One word becomes a card worth keeping.

Not a dry dictionary entry — a small, thoughtful card built for a child, with everything they need to truly learn the word and nothing they don't.

The definition — clear and sourced, the thing to memorize.
A kid-friendly explanation — the same idea, in words a child owns.
How to say it — a simple respelling, never confusing symbols.
The sentence from the book — the word in the world it was met.
Synonyms — the neighborhood the word lives in.
Try it yourself

The original prototype — still playable.

This is the very first interactive prototype that started it all. We kept it exactly as it was, so you can tap through the whole experience — capture, library, flashcard review, and the story of where the idea began.

Tap the BookWords icon to launch · everything is interactive · nothing to install
How it works
The only step
Capture the word — and keep reading.
Point the camera at the word on the page. BookWords shows you the word it sees, you confirm it with one tap, and the story moves forward. That's it.
Meanwhile, in the background
The card builds itself
A real dictionary definition, a kid-friendly explanation, pronunciation, and synonyms — assembled quietly while you read.
The library grows
You approve each card, and it joins your child's vocabulary library — organized and ready whenever you are.
Practice comes later
Review the cards together after the story — and one day, order them as professionally printed flashcards. (planned)

One step. The story never stops.

Turn the words they discover into words they remember. BookWords helps parents capture unfamiliar words from physical books and turn them into vocabulary cards — so the words your child discovers become words they understand, without ever breaking the story.

How it started

It began at bedtime, one hard word at a time.

Every parent who reads with a child knows the pause. You're a few pages into the story, the room is quiet, and your child hits a word they don't know — craning, luminous, reluctant — and looks up at you.

In that instant you have two bad options: stop the story to explain and lose the moment, or skip the word and lose the chance to teach. What if there were a third way — one that captured the word in a heartbeat and kept the story going?

That question became BookWords. Point your phone at the word, and it quietly becomes a flashcard your child can review later — a definition they can understand, the sentence it came from, how to say it, words like it. The reading never stops. The learning never gets lost.

From one family

BookWords started with a dad, a daughter, and a bedtime story.

Colby Foster built BookWords because he wanted a better way to help his daughter with the words she stumbled on while they read together. No product team, no funding — just a real problem at bedtime, and the conviction that there had to be a better answer than "we'll look it up later."

Today BookWords is a real, native iPhone app — refined week after week through real reading sessions with the family it was built for.

View the product development story behind one parent's frustration