Commonplace is a personal reading journal I built and use myself—it tracks the books I’m reading, collects quotes and notes as I go, and runs the voting and ratings for my book club. Everything lives in a single file in your browser: no account, no server, no analytics. It works offline once installed, and nothing leaves your device except the two things you explicitly ask it to send out (an ISBN to look up a cover, or your own notes to Claude if you turn on AI summaries).
Installing it
Commonplace is a Progressive Web App—there's nothing to download from an app store, and once it's added to your home screen it opens full-screen with no browser chrome, exactly like a native app.
On iPhone: open the app link in Safari specifically (Chrome and Firefox on iOS can't install PWAs). Tap the Share icon, scroll down to Add to Home Screen, and confirm. That's it.
On Android: open the link in Chrome, tap the three-dot menu, and choose Add to Home screen (Chrome will sometimes offer this automatically via a banner at the bottom of the screen).
Click for full documentation and explanation of how to install and use the app.
What it actually does
Add a book by ISBN and Commonplace pulls the title, author, cover, and other details automatically from Open Library. From there:
Progress. Update your current page and it tracks a full reading history—not just percent complete, but a log of every session. It also handles anthologies properly: if you're reading one essay inside a collected volume, you can set the page range for just that piece, and progress is calculated within it rather than against the whole book.
Notebook. Quotes and notes are attached to specific books, support Markdown, and are searchable across your whole library. The home screen surfaces a quote of the day, seeded from the date, so it changes on its own.
Book Club. Set a current read with a meeting date, log past reads with per-member ratings, and run votes on what to read next using a proper ranked-choice (Borda count) tally rather than a simple show of hands.
Stats. A yearly reading-goal tracker with pace, plus totals across books, quotes, and notes.
AI Insights. Optionally, with your own Claude API key, generate a thematic analysis or chapter summary, or synthesize your own notes into something coherent. This is the one feature that talks to a server—it sends only the book title and the notes you're asking about, directly to Anthropic, and nothing else.
Your data
Everything is stored locally—there's no account and nothing syncs to a server. That also means you are the backup: export your library as a JSON file periodically (there's a gentle reminder built in if it's been more than two weeks), especially on iOS, where Safari can occasionally clear site storage on its own. The app keeps a second copy in a harder-to-evict storage layer and will try to recover automatically if that happens, but an export you're holding yourself is the only real guarantee.
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