Built around the moment you meet a new word.

Folio Reader combines a practical PDF reader with vocabulary support, on-device language tools, and review workflows.

Reading

Open PDF documents from your device, file managers, browsers, or sharing apps. Text-based PDFs use direct extraction; scanned PDFs can use OCR.

Smart highlighting

Vocabulary Assistance can automatically highlight challenging words on the current page. Highlight density can be tuned to fewer, balanced, or more words.

Definitions, examples, pronunciation

Tap a highlighted word to access its cached or dictionary-backed meaning, pronunciation and related information without abandoning the document.

Offline translation

Download an on-device English-to-Hindi ML Kit model and translate without a network connection. The app supports choosing the target language from the supported set.

Vocabulary and review

Save words from reading, track learning status, and review them through Active Spaced Repetition, interactive flashcards, and Daily Quick Quiz sessions.

Optional AI explanations

Folio can optionally request AI explanations using a Gemini API key configured by the user. This is separate from the offline dictionary, OCR, vocabulary storage, and on-device translation features.

Classroom mode

Nearby Connections can support shared word activities between nearby devices. This feature is optional and requires the relevant Android connectivity permissions.

Export

Export saved vocabulary as readable text or Anki-compatible CSV for use in another study workflow.