JP Lens

JP Lens turns any app on your phone into a Japanese reading tool. Tap the floating button and it captures what's on screen, recognises the Japanese text, and lays tappable boxes right on top of it — so you can look words up without leaving your game, manga reader, or browser.

Everything runs on your device. No account, no ads, no analytics, no servers. JP Lens doesn't even request the Internet permission.


HOW IT WORKS

1. Grant the screen-capture and "display over other apps" permissions.
2. Open any app with Japanese text in it.
3. Tap the floating button to scan the screen.
4. Tap the text you want, and the breakdown opens on top of it.

Hold the floating button to switch modes or stop — no need to reopen JP Lens.


TWO SCAN MODES

• Full screen — scans everything on screen and outlines the Japanese it finds. Tap any sentence to open its breakdown.
• Crop — freezes the screen so you can drag a box around just the part you care about. Ideal for a single manga bubble or a busy UI.


INSIDE THE BREAKDOWN

The sentence comes back split into words, each one underlined and tappable.

• Tap a word to expand its full dictionary entry: every meaning, part-of-speech and usage tags, notes, alternate spellings and readings — plus the meaning and JLPT level of each kanji in it.
• JLPT levels N5–N1 are labelled wherever they're known.
• Kana reading of the whole sentence.
• Romaji (Hepburn), read from the actual pronunciation, so particles come out as wa, e and o.
• Japanese to English translation, computed on your device.

Reading, romaji and translation each have their own switch on the home screen, so you can keep the breakdown as light or as detailed as you like.


WHAT'S INSIDE

• Offline Japanese OCR that handles horizontal and vertical (manga-style) text
• A comprehensive offline dictionary — JMdict, plus KANJIDIC2 for kanji meanings and readings
• On-device Japanese to English translation (FuguMT) — no server, no waiting
• JLPT N5–N1 labels on words and kanji
• One-tap flashcards: send any word to AnkiDroid together with its dictionary entry, its kanji, the sentence you found it in, and that sentence's translation (requires AnkiDroid; entirely optional)
• A short built-in walkthrough that shows each mode in action


PRIVATE BY DESIGN

JP Lens has no servers and makes no network requests — it doesn't hold the Internet permission at all. Screen captures are processed in memory and discarded immediately: never saved, never uploaded.

There's exactly one way anything can leave your phone, and it's your call. Under each translation is a "Google Translate" link; tapping it opens that one sentence in your web browser at translate.google.com. Nothing is sent unless you tap it.

JP Lens is free and open source.


GOOD TO KNOW

• Offline translation has real limits. Online translation costs money to run, so this free app keeps everything on-device — and when a translation looks off, the Google Translate link is one tap away.
• Manga panels that mix horizontal and vertical text can confuse the OCR. Zoom into the panel, or use Crop mode to take one bubble at a time.


PERMISSIONS

• Display over other apps — to show the floating button and the overlay.
• Screen capture (asked each session) — to read the text currently on screen.
• Notifications — for the required "capture active" notice while running.
• AnkiDroid access (optional) — only if you use the flashcard feature.


Made for learners who want to read real Japanese — games, visual novels, manga, websites — and look things up the moment they get stuck.


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Dictionary data: JMdict / KANJIDIC2 © the Electronic Dictionary Research and Development Group (CC BY-SA 4.0). JLPT lists by Jonathan Waller (CC BY 4.0). Translation model: FuguMT by Satoshi Takahashi (CC BY-SA 4.0).