Side-by-side bilingual EPUB reader with synchronized audiobooks, inline dictionary, and spaced‑repetition vocab export; supports sideloaded files and Whisper‑like alignment.
Platform: web
Many language-learners want to read a text in two languages simultaneously and, ideally, listen to a perfectly-synced audiobook. Current mainstream solution (Amazon Whispersync) only works for books bought from Amazon and often in one language. Indie learners who own their own EPUB + MP3 have to juggle several tools (Calibre, aeneas, dictionaries, Anki, etc.).
Proposed product: Web app that accepts any EPUB in two languages + an audiobook, auto-aligns them (Whisper-like or aeneas), shows the two texts side-by-side, plays audio in sync, pop-up dictionary, and exports unknown words to spaced-repetition (Anki CSV).
| Evidence source | Signals |
|---|---|
| Hacker News ask (id 45075127) | User looking exactly for this; replies mention only one partial solution (Readini). |
| Reddit threads (r/languagelearning, r/kobo, r/selfhosted, etc.) | Multiple recurring posts (May 2023, Aug 2023, Mar 2024, Mar 2024, Sept 2024) asking for “parallel reading apps”, “bilingual EPUB side-by-side”, “self-hosted Whispersync”. Up-votes and long comment chains show pain-point. |
| HN Show HN 38747710 (“Storyteller – self-hosted synced narration”)... |