01
Open a book
Import your own EPUB, PDF, TXT or DOCX, take a photo of a printed page, or start with one of the classics in the library.
E-reader and language guide
Read books in the language you’re learning.
Open a book, tap a word and understand it right away. New words come back for review just when you start to forget them.
No ads. English, German, French, Spanish, Italian, Russian and Czech.
How it works
A book is the best textbook.
No made-up sentences about where the station is. You learn from a story you actually want to finish.
02
Tap a word
See what the word means in this very sentence, plus a short, human explanation of the grammar at your level.
03
Review wisely
Saved words come back as flashcards, together with the sentence from the book, right when you need to review them.
Try it yourself
Tap an underlined word.
This is what reading in Trailerbook feels like. Pick a language and tap any underlined word. You’ll see what it means in this exact sentence and why it has this particular form.
- Meaning in context, not just a dictionary list
- Grammar explained in plain English, no jargon
- One tap turns it into a flashcard
A few words here are prepared in advance. In the app you can ask about any word or whole sentence in any book.
Als Gregor Samsa aus , in seinem Bett zu einem ungeheueren verwandelt.
L’année 1866 par un événement bizarre, un phénomène inexpliqué et que oublié.
En un lugar de la Mancha, de nombre no quiero , que un .
, что : дама .
erwachte
B1
In this sentence: woke up
Simple past (Präteritum) of erwachen. In a clause starting with als (when), the verb goes to the very end.
Flashcards: 0
Translate the whole sentence
When Gregor Samsa woke one morning from restless dreams, he found himself transformed in his bed into a monstrous insect.
The reader
The book adapts to you, not the other way round.
Is the chapter too hard? Want to hear it? Or see the original next to a translation? The reader has tools you would otherwise look for in five different apps.
Text adapted to your level
Not ready for this chapter yet? Have it retold more simply, for example at A2. The plot stays the same, only the words and sentences fit you. And when you want more, the same chapter can be enriched instead. One tap takes you back to the original.
In my younger and more vulnerable years my father gave me some advice that I’ve been turning over in my mind ever since.
When I was young, my father gave me some advice. I still think about it today.
Original and translation side by side
Dual reading shows a paragraph in the original with your language right next to it. Great for the first chapters, while you find your feet, or for the moments when you want to be sure you understood correctly.
Deutsch
Als Gregor Samsa eines Morgens aus unruhigen Träumen erwachte, fand er sich in seinem Bett zu einem ungeheueren Ungeziefer verwandelt.
English
When Gregor Samsa woke one morning from restless dreams, he found himself transformed in his bed into a monstrous insect.
An X-ray of difficulty
CEFR X-Ray colours paragraphs by difficulty. Green ones you can handle right away, yellow ones are a challenge, and purple ones are literary treats for later. At a glance you see where to slow down and where to simply enjoy reading.
A1–A2
The dog was big and black. It sat by the door all day.
B1–B2
Although it was late, she decided to walk home through the park.
C1+
The house stood in brooding silence, its shutters drawn like heavy eyelids.
Cinema reading and read-aloud
The book reads to you aloud while the text lights up smoothly, karaoke-style, so your ears and eyes work together. Choose a voice, a speed and gentle background sounds such as rain or a fireplace. At night there is a sleep timer, and for walks there is hands-free listening.
It was a dark and stormy night; the rain fell in torrents.
1.0×
Conjugation and patterns
Found a verb in a strange form? Open its table straight from the reader. You’ll see tenses, persons and patterns, and know why the sentence says fand and not findet.
findento find · irregular
| Präsens | Präteritum | |
|---|---|---|
| ich | finde | fand |
| du | findest | fandest |
| er/sie/es | findet | fand |
| wir | finden | fanden |
Perfekt: hat gefunden
Sentence tree
Breaks a complex sentence into parts, so you can see what belongs to what.
Talk to a character
After a chapter you face a dilemma with a character and answer in the foreign language. You get feedback on your grammar.
Literary studio
Building sentences and the fine differences between words that mean almost the same.
Colour annotations
Highlights and notes in colours, with export to Anki and Markdown.
Bookmarks and notes
Everything you write down about a book, in one place.
Offline reading
No internet? Keep reading. Translations you already have are stored on your phone.
Inside the app
Calm. Thoughtful. Yours.
Dark and light themes, a typeface made for long reading and nothing to distract you. Tap a screen to enlarge it.
Reader
A typeface for long reading, chapter progress and read-aloud.
Learning path
Lessons step by step, including your own chapters.
Moving chapters
Grab a chapter and drag it where it belongs.
Review
Words from your book, with a combo for every streak of right answers.
Lesson complete
XP, accuracy, best run and streak.
Your own chapter
From a photo, a file or your notes.
Light theme
For reading during the day or in the sun.
Review in light mode
Three buttons, and you know when the word comes back.
Perfect session
Everything right and the daily goal reached.
Library
Your current book, daily goal and word of the day in one place.
Practice
Review you’ll actually enjoy.
You won’t just look at words. You’ll build them, catch them and race the clock, always with the sentence from the book where you met them.
Flashcards at the right moment
Trailerbook remembers what comes easily to you and what doesn’t. A word you know comes back in a week, a word that keeps slipping away comes back tomorrow. You rate with three buttons, and your answer doesn’t have to be perfect: a small typo or a missing accent won’t count against you.
Speed Recall
How many words can you get in a minute? A quick warm-up round.
Sentence builder
Put jumbled words back in the right order. You learn word order without memorising rules.
Gravity Fall
Words fall from the sky and you catch them with the right translation before they land.
Match grid
Twelve tiles, a stopwatch and one job: match words with their meanings as fast as you can.
Mistakes inbox
What you got wrong comes back in a short two-minute fix, so mistakes don’t get forgotten.
Streak, combo and daily goal
XP for every lesson, a combo for a run of right answers, and at most one gentle reminder a day.
For school
Present perfect at school? It’s in the app.
Write what you are learning right now and add your material. The lesson is built from your textbook, not from a generic template.
- Take a photo of one or more pages; the text is read right on your phone
- Or upload a PDF, a document or your notes
- Explanation, examples and eight exercises in moments
- Place the chapter on your learning path exactly where it belongs
Sharing
A sentence that caught you? Share it.
Select a short quote and Trailerbook turns it into a card for Instagram or your stories, with the translation and the book title. Choose from three styles: Dark, Minimal and Velvet.
- 4 : 5 format, ready for social media
- The source is added automatically, quotes are at most two sentences
- Save to your gallery or send it straight on
Kids mode
A world of its own for young readers.
Kids get their own, simpler world: picture books, short quizzes and a buddy they dress up with the points they collect. A parent turns kids mode on and has their own overview behind a parental lock.
- Picture booksA reader with illustrations that doesn’t overwhelm children. Kids choose which language they want to read in.
- Book quizzesFind-the-word games and questions about the story, suited to their age.
- A buddy with outfitsPoints from lessons unlock new outfits.
- Several kids, one phoneEach child has their own profile with age and language.
- SafeNo ads and no purchases. Only a parent can unlock the settings.
7
languages to learn
English, German, French, Spanish, Italian and Russian. And Czech, too.
A1–C2
from beginner to advanced
Choose your level yourself or take a short test. Each language can have its own level.
6
book formats
EPUB, PDF, TXT, DOCX, CBZ comics and photos of pages. Illustrations stay in colour.
6
app languages
Czech, English, German, French, Spanish and Russian.
“One chapter a day. In a year, a whole library in a language you couldn’t understand before.”Trailerbook
Who Trailerbook is for
Even for people who think they’re no good at languages.
Lots of people have tried reading in a foreign language, felt stupid after three pages and closed the book. It is rarely about talent. Usually it is a missing piece of grammar that nobody ever explained properly.
Trailerbook is patient. It explains why a word changes as many times as you want, and never makes you feel you “should know this by now”. You start with a story you enjoy, and the grammar comes along with it.
FAQ
What people ask.
Is Trailerbook free?
The core features are free and ad-free. Advanced features will be part of a subscription via Google Play. We’ll publish exact prices at launch.
Can I read my own books?
Yes. Import EPUB, PDF, TXT, DOCX or a CBZ comic, or take photos of printed pages. Your books stay on your phone. They are stored in the cloud only if you sign in to sync.
Does it work offline?
Reading, flashcards and review all work offline. The app remembers translations you already have. New explanations from the assistant need a connection and are filled in automatically once you’re back online.
What level is it for?
From complete beginners (A1) to advanced (C2). You can have the text simplified, and grammar explanations follow your level. Not sure of your level? A short test at the start finds it.
Is it suitable for children?
Yes, there is a separate kids mode with picture books and quizzes. It has no ads or purchases, and only a parent can unlock the settings. Parents can see how their kids are doing.
What about privacy?
The app shows no ads, we don’t sell data, and photos of pages are read on your phone. When you ask about a word, only the selected text is sent to our server, and it is not stored there. Details are in our privacy policy (in English and Czech).
When and where can I download it?
Trailerbook launches first for Android on Google Play. Want to be among the first to know? Write to us.
Coming to Google Play
Your next book is waiting.
Trailerbook is on its way to Google Play. The core features are free, with no ads.
Let me know at launch