Underline: Book Quotes & Notes

You underline a line in a book. You copy it into a notebook. Then the notebook stays at home, exactly when you want to find that passage again.

Underline is your personal quote notebook for the printed books you read. Save the lines you underline, keep them organized by book and page, and find any of them in seconds, wherever you are.

SAVE A PASSAGE IN SECONDS
• Point your camera at the page. Text is recognized right on your device
• Tap to select just the sentences you want, then save
• Prefer typing? Add any quote manually
• Add the page number, a personal note and tags

BUILD YOUR BOOKSHELF
• Add books by scanning the ISBN barcode or searching by title or author
• Every quote is kept with its book, author and page
• Mark favorites to keep your most loved lines one tap away

FIND ANY LINE, ANYWHERE
• Full-text search across every quote and note
• Filter by book, tag or favorites
• Your reading notes travel with you, no paper notebook required

SHARE THE WORDS YOU LOVE
• Turn a quote into a clean, beautiful card
• Share it to Instagram Stories, messages or anywhere else

YOUR DATA, YOUR FILES
• Back up your whole library to a single .underline file and restore it anytime
• Export to CSV or Markdown, ready for Notion, Obsidian or a spreadsheet

PRIVATE BY DESIGN
• No account, no sign-up
• Your quotes are stored on your device, not on our servers
• Works offline. The internet is only used when you look up a book

Text recognition works with Latin-alphabet languages (English, Spanish, French, German, Italian, Portuguese, Turkish and more), plus Japanese. Handwriting is not supported.

UNDERLINE PRO (OPTIONAL)
• No ads
• Every quote card style, PDF export of a book's quotes and full reading insights
• Monthly or yearly subscription (the yearly plan starts with a free trial), or a one-time lifetime purchase
• Your books and quotes stay free and unlimited without Pro

Underline is free to download. Start your quote journal with the book on your nightstand.

Recent changes:
• Mark up page photos: highlighter, underline and pencil in 7 colors. Marked lines become your quote.
• Underline finds your real highlighter marks in a photo and selects those lines for you.
• Zoom in to mark small print with ease.
• New Page card: share a quote together with your marked page.
• New Pages tab on every book.
• Reading time: a timer while you read and the total for each book.
• Light, dark or system theme.