Use case

A commonplace book for everything you read

Highlights, notes, tags and review · Android · Free

The short answer

GemReader is a free Android reader that keeps a commonplace book as you read. Highlight a passage and it becomes an entry; tag it and it files itself under a theme; add a note and your thought stays attached to the words. Every entry from every book sits in one searchable list, and the best ones come back for review on a spaced-repetition schedule.

It works offline, needs no account, and exports everything as Markdown whenever you want it somewhere else.

Why a paper commonplace book stops working

The practice is old and sound: copy out what matters, arrange it under headings, reread it. What breaks is the copying. Transcribing a paragraph by hand takes minutes, so most passages never make it into the notebook, and the ones that do are filed under whatever heading seemed right that evening.

Highlighting in an ebook fixes the copying and loses everything else. The passages are captured, then scattered across a hundred books with no headings, no index and no reason to ever see them again.

The old method, one step at a time

Copying the passage outHighlight it. Six colours, and each colour can be renamed per book — Argument, Evidence, Quote, To look up — so the colour is already a heading.
Writing under a headingTag it. Any highlight or note takes any number of tags, and a tag cuts across every book in the library, which is what the headings in a commonplace book were for.
Your own commentaryAttach a note. Notes are typed in Markdown and stay anchored to the passage, so the thought and the text it answers are never separated.
The index at the backSearch the gems list. Every highlight and note from every book sits in one list, searchable by word and filterable by tag, book and colour.
Rereading the bookReview. Highlights become cards on a spaced-repetition Review page, so the passages you marked come back a day, a week, a month later instead of never.
Copying out for a friendMake a quote card. A passage becomes an image with the book and author set beneath it, ready to send.

What it won’t do

  • Collect from everywhere. Entries come from books you read in GemReader — EPUB, PDF, MOBI, AZW3 and comics. Web articles and podcasts need another tool.
  • Sync through a cloud. There is no server. The library, gems included, moves between devices with Gem Beam over local Wi-Fi, and the Markdown export is your off-phone copy.
  • Run on iPhone yet. GemReader is on Android; the iPhone and iPad version is in testing.

Bringing an existing collection

Years of Kindle highlights don’t have to stay behind. The free Kindle Highlights to Anki converter turns My Clippings.txt into a Markdown file of quotes, grouped by book, or a flashcard deck that GemReader’s Review page imports.

For the study side of the same habit, see how to turn ebook highlights into flashcards and quote cards.

Questions people ask

A notebook of passages worth keeping, copied out while reading and arranged under headings so they can be found again. Erasmus taught it as a study method, John Locke published a system for indexing one, and readers kept them for centuries as a personal anthology of everything they had learned from books.

Yes, for what you read in it. Highlights are the entries, tags and renamable colours are the headings, Markdown notes are the commentary, the library-wide gems list is the index, and the Review page brings entries back with spaced repetition. It works offline, has no account, and is free with no paid tier.

Yes. Highlights and notes export as Markdown — one file you can open in Obsidian, Notion or any text editor — or as an Anki deck. Your entries are never locked inside the app.

Not as gems, but you can bring them along. The free Kindle Highlights to Anki converter turns a Kindle's My Clippings.txt into a Markdown file of quotes or a flashcard deck, and GemReader's Review page imports that deck. DRM-free Kindle books (AZW3, MOBI) can also be imported and highlighted directly.

No. GemReader has no server and no account; everything stays on the phone, encrypted. Gem Beam moves the whole library, gems included, to another device over local Wi-Fi, and the Markdown export gives you a copy anywhere you like.

The reader built for studying

Textbooks, lecture PDFs and workbooks in one library. Highlight as you read, then study those highlights as flashcards — without exporting anything or leaving the app. Free, no ads, no account.

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