Hoshi Reader: Android app for reading Japanese e-books while learning vocabulary

Hoshi Reader is a new Android app for reading Japanese EPUB e-books. It lets you look up unknown words instantly and save them to a flashcard app, making it a handy all-in-one tool for Japanese learners.

Hoshi Reader combines e-book reading with vocabulary study on Android. When you tap an unfamiliar word, it shows a definition using a Yomitan-style lookup — no need to switch to a separate dictionary app. You can also save words straight to Anki, a popular flashcard app, in a process learners call 'mining.'

The app also supports audiobook read-along mode, where audio plays while the matching text is highlighted, helping with listening and reading at the same time. It works on e-ink devices like dedicated e-readers, not just regular smartphones. This is a niche language-learning tool with no direct connection to AI agent development or cost reduction.

Key points

  • Reads Japanese EPUB e-books on Android
  • Tap any word for an instant dictionary definition (Yomitan-style)
  • Automatically saves words to Anki flashcards (called 'mining')
  • Audiobook read-along mode syncs audio with highlighted text
  • Compatible with e-ink screen devices

Quick term guide

Android app
A mobile application that runs on Android smartphones, like those made by Samsung or Google.
Android
The main operating system used on most non-Apple mobile phones.
Yomitan
A dictionary tool that shows the meaning of a Japanese word the moment you hover over or tap it.
mining
Using computer power to process transactions and earn digital currency as a reward.
ports
Numbers that apps use so they can talk on the same computer without clashing.
niche
A very specific, narrow segment of a market or customer group.
AI agent
An AI program that can inspect information and suggest what to do next.
flashcards
Simple study cards with a question on one side and the answer on the other, used for memorization.
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