Books open new languages.
Read the original, even above your level. Tap any sentence for a translation and a clear AI breakdown, then save new words as flashcards and review them until they stick.
- EPUB
- FB2
- Link
Your own books and articles · reading and translation free, with no limits
What it does
Help with the hard parts, right on the page
Looking a word up in another app costs you the sentence you were in. In Folioki the translation, the explanation, and the flashcard all open on the page you're reading.
Bring your own reading
A novel, a news story, a blog post, a page you paste in. Folioki opens EPUB, FB2, and PDF books, web articles from a link, and plain text. You pick what to read, and none of it has to come from a shop.
Tap to translate
Tap any word, phrase, or sentence, and its translation appears right under it. The translation runs on your device, so it costs nothing and works offline.
Break down the hard parts
When a translation isn't enough, ask for a breakdown. The AI explains the meaning, the grammar, and the context in plain words, in your own language. Still confused? Ask a follow-up in your own words and keep asking until the sentence makes sense.
Flashcards in one tap
Save a word straight from the text, and Folioki writes the card in seconds: the translation, an example, the sentence you found it in, its forms, and its pronunciation. Ask the AI for a simpler example, or edit the card yourself.
Remember what you learn
Memory research shows you keep a word longer when you review it at growing intervals. Folioki brings each word back when you're about to forget it, so hard words return sooner and easy ones wait for weeks — how spaced repetition works.
One library, every device
Your books, your place in each one, and your deck sync across iPhone and iPad. Start a chapter on the train and finish it on the sofa.
How it works
Read, understand, save, remember
You build your vocabulary from texts you care about, and every word keeps the sentence you met it in. A word with a story behind it is easier to recall than the same word from a prebuilt deck or a frequency list.
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Add what you want to read
A book file, an article link, or a passage you paste in. Pick the language you want it explained in, and start reading.
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Ask what it means
Tap anything you don't know. Take the translation and read on, or ask the AI why the sentence works that way and keep asking until it clicks.
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Save it as a card
One tap turns the word into a flashcard, with the sentence you met it in already filled in. Change anything you like, or add it to your deck as it is.
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Review a few minutes a day
Your deck shows each word on the day you're about to lose it. You recall the answer yourself, mark how easily it came back, and Folioki schedules the next review — how to answer a card.
Pricing
Free to read. Pay for the thinking.
Reading, on-device translation, your library, and your whole deck are free, with no limits. A subscription buys more AI work each day: the breakdowns, translations, and cards a language model writes for you.
Free
Free
Just to try it
- Unlimited reading and on-device translation
- A dozen or so AI breakdowns a day
- Your whole deck, reviewed as often as you like
Plus
$2.99 / month
If you read every day
- Several times as many breakdowns, translations, and cards a day
- A stronger AI model for fuller, more accurate answers
- Stuck on a sentence? Ask in your own words and get a considered answer
Premium
$7.99 / month
If you read a lot at a time
- Everything in Plus
- The daily limit raised again, high enough to stop counting
- Follow-up answers explain why the sentence works that way
Prices are shown in your own currency in the app, and may differ from the US figures above. Subscriptions renew monthly until canceled, and you cancel them in Settings on your device.
Questions
Before you download
What if the text is far above my level?
You can still read it. Tap a sentence for its translation, ask the AI to break down whatever still doesn't make sense, and save only the words worth learning. The harder the text, the more you'll ask at first, and the fewer questions you'll need as your vocabulary grows.
Which languages can I use it with?
Read in, and translate into, German, English, French, Spanish, Italian, Russian, or Ukrainian. Explanations come back in the language you chose to translate into, so you never get a grammar lesson in the language you're still learning.
Where do the books come from?
From you. Folioki opens EPUB, FB2, and PDF files from your device or iCloud Drive, pulls the readable text out of any article you give it a link to, and takes plain text you paste in. There's no catalogue and nothing to buy inside: you learn from the things you were going to read anyway.
Does it work offline?
Reading and tap-to-translate do. The translation runs on the device itself, so a plane, a tunnel, or a countryside train changes nothing. AI breakdowns and the cards the AI writes need a connection, because that work happens on our server.
How does Folioki decide when to show me a word again?
It learns how you forget. Each time you answer a card, Folioki updates its estimate of how well you know that word and schedules the next review for the moment your chance of recalling it drops to the level you chose. The gaps between reviews grow as the word settles in. That is spaced repetition: widening intervals that follow your own memory instead of a fixed drill.
The scheduler behind it is FSRS, a modern, openly researched algorithm that fits a curve to your actual answers instead of giving everyone the same intervals. Words you keep getting right disappear for weeks. Words that trip you up come back tomorrow. In practice that means a few minutes a day, and a queue that ends. The longer version is here: spaced repetition, and the reading that feeds it.
Can I export my cards?
Not yet. The deck lives in Folioki, where you review each card with the sentence and context it came from, and that context is most of what makes the cards worth answering. If you want to take your cards elsewhere, write to us and say so: requests like that shape what we build next.
Is what I read private?
Your library is your own business. When you ask about a line, that line is what gets sent, and only to produce your answer. We don't pass anything about your reading to anyone else or turn it into advertising. The Privacy Policy sets out what we keep and for how long.
What state is the app in?
It's on the App Store, and the people building it read in it every day. Write to [email protected] and tell us what breaks.
The book you want to read, in the language you're learning.
Free on the App Store. Bring a book you've been putting off.
