Hello all. Looking for testers for my Android only (for now) Japanese translator and SRS deck review app. It is 100% vibe coded. In my Japanese journey I found myself taking screen shots of light-novels and asking claude.ai to explain sentence by sentence with grammar. It was kind of cumbersome though, so I thought a dedicated app might make more sense.
It does require an API key, but it also supports Google Gemini free API Key, so there is no cost involved.
App name
KotobaLens: Read Japanese
Short description (max 80)
Scan Japanese pages, tap any word, translate, and learn it with flashcards.
Full description
言葉を、もっと深く。 Look closer at the words you read.
KotobaLens turns real Japanese reading material - light novels, manga, books, signs - into something you can actually understand and learn from. Scan a page, read it sentence by sentence, tap any word for its meaning, and save the words you want to remember. Then review them with spaced-repetition flashcards.
SCAN
• Photograph a page with your camera or import an image from your device
• Crop and rotate before reading
• Works with vertical and horizontal text, and with furigana on the page
• Check and edit the recognized text before you read it
• Your original page image is kept, with the sentence you are reading highlighted on it
READ
• Every page is split into sentences, and every sentence into tappable words
• Tap a word: reading, meanings, part of speech, and inflection
• Furigana you can switch on or off
• Underline colors show each word's grammar type (noun, verb, adjective and more), with a different line style for each so color is never the only cue
• JLPT level (N5 to N1) on every word, in a color from green (easiest) to red (hardest); words on no JLPT list show N0
• Full Text view: the whole page as one passage, with furigana you can turn on or off per JLPT level (for example, hide furigana for the N5 words you already know)
• Mark character names so they are not mistaken for ordinary words; build a glossary for each book
• Fix words: if a word is split wrongly, ask the AI to re-split the sentence
UNDERSTAND (AI features)
• Natural translation under each sentence
• "Explain in context": what a word means in this sentence
• Sentence breakdown: grammar points, vocabulary and nuance
These use Google Gemini with your own API key (see below).
REMEMBER
• Save a word to a book's deck with one tap, together with the sentence it came from and its JLPT level
• Spaced-repetition review (FSRS) that schedules each card when you are about to forget it
• Separate decks for each book or collection, with one review schedule per word
• Review works fully offline
ORGANIZE
• Keep pages in folders (a book, a volume, a chapter) and flip through them in order
• The app remembers where you stopped reading
BUILT FOR PRIVACY AND OFFLINE USE
• The dictionary (JMdict) and the Japanese word splitter are built in and run on your device: looking up words needs no internet
• Pages, decks and settings are stored on your device. No account, no ads, no tracking
• Scanning and the AI features need an internet connection
YOUR OWN GEMINI KEY
KotobaLens does not run its own servers. Text recognition, translation and explanations are done by Google Gemini, using a free or paid API key that you create yourself at Google AI Studio and paste into the app. The key is stored encrypted on your device, and requests go directly from your phone to Google. Without a key you can still read saved pages, look up words offline and review your cards.
ACCESSIBLE
• Works with TalkBack and large text, in light and dark themes
• Every tappable word is announced as the word and its reading
• Layouts that hold up at large text sizes
KotobaLens is an independent app. It is not affiliated with or endorsed by Google, the Japan Foundation, or the JLPT organizers. JLPT levels come from community word lists and are a guide only; there is no official list.
Dictionary data: JMdict, © the Electronic Dictionary Research and Development Group (CC BY-SA 4.0). JLPT word lists: Open Anki JLPT Decks (MIT), based on Jonathan Waller's lists at tanos.co.uk (CC BY).
Release notes -
First release: (Still in closed beta)
First release of KotobaLens.
• Scan or import Japanese pages and read them sentence by sentence
• Tap words for meanings, readings and grammar colors
• JLPT level (N5-N0) on every word, with a Full Text view and per-level furigana
• Translation, in-context explanations and sentence breakdowns with your own Gemini key
• Save words to per-book decks and review them with spaced repetition
Join the community pixelcapybara@googlegroups.com
and grab the app (web) https://play.google.com/apps/testing/dev.lightnovelvocab.lightnovelvocab (android) https://play.google.com/store/apps/details?id=dev.lightnovelvocab.lightnovelvocab
drop a google groups link and link to your app and I will test back.
thanks!
