Getting Started
Adding a book
Tap Add Book in the tab bar. You have three options:
- Scan a barcode – point your camera at the ISBN barcode on the back of a book. The title, author, cover image, and other details are filled in automatically.
- Type an ISBN – enter the 10- or 13-digit ISBN number and tap Lookup to fetch book details.
- Manual entry – type in the title, author, and any other details yourself. No ISBN required.
Tracking your reading
Each book has a reading status: To Read, Reading, Read, or Did Not Finish. Change the status from the book detail screen or the Library listing.
Notes and quotes
Open any book and use the Quotes and Notes tabs to save passages and thoughts. For quotes, you can photograph a page and Lectr will extract the text using on-device OCR – no data leaves your device. You can also add a page number and a personal comment to each quote. The Notes & Quotes tab shows all entries across your entire library.
Colour markers
Notes and quotes can be colour-coded so you can visually organise your reading at a glance.
Both notes and quotes display on neutral cards with a coloured vertical strip along the left edge. Choose from four colours – yellow, blue, pink, or green – using the colour circles in the editor. For notes the strip colour defaults to yellow; for quotes it is optional. Tap a colour to assign it, tap again to remove it, or use the × button to clear your selection.
On the Notes & Quotes tab you can filter by colour to quickly find entries – tap one or more colour circles in the filter bar to show only matching notes and quotes.
Tags and organisation
Create tags (e.g. "Fiction", "Work", "Favourites") and assign them to books. In the Library, filter by one or more tags. You can switch between matching any selected tag or requiring all selected tags. Swipe left on a book to delete from the Library page, or use the menu on the book detail page.
Bulk operations
Long-press any item to enter bulk edit mode. Tap additional items to add them to your selection, then use the action bar at the bottom of the screen.
- Library – change reading status, add or remove tags, or delete multiple books at once. When all visible books are selected, a banner offers to select all books matching your current filters.
- Notes & Quotes – select and delete multiple entries across your library.
- Notes and Quotes tabs (within a book) – select and delete multiple entries.
- Manage Tags – tap to select tags, then delete in bulk. Removing a tag detaches it from all books.
Every bulk deletion requires confirmation before anything is removed.
Star ratings
Rate books from 1 to 5 stars on the book detail screen. Use the Library filter to find books by rating.
Cross-references
Link related books together using cross-references. Open a book, scroll to the Cross-References section, and tap Add Cross-Reference to search for and link another book from your library. You can add an optional comment to describe the connection (e.g. "Same author", "Similar themes").
Cross-references are bidirectional – linking Book A to Book B automatically shows the link on both books. Swipe left on a cross-reference to delete it, or tap to edit the comment.
Search, sort, and filter
The Library screen has full-text search across titles and authors, sorting options (title, date added, rating), and filters by reading status, rating, and tags. The Notes & Quotes tab also supports search, date sorting, and colour filtering. You can set a default sort order for both Library and Notes & Quotes in Home → “…” → Settings.
Thematic search
On the Notes & Quotes tab, tap the Thematic chip to search by concept instead of exact keywords. Type a theme like “identity”, “grief”, or “power” and Lectr finds passages that relate to that concept — even if they never use that exact word.
When you activate thematic search, your search term locks in as a scope (shown as a purple chip). The search bar then lets you narrow within those thematic results using exact keywords. Tap the × on the purple chip to clear the scope and return to normal search.
Thematic search works best with single concepts — try “power”, “identity”, or “grief” rather than multi-word phrases. Single words expand into a rich network of related terms; phrases search for the exact text.
Thematic search is multilingual — it works in the language you type. All analysis runs entirely on your device using Apple’s built-in language tools. Nothing is sent to a server.
Search operators
The Library search bar supports special operators that let you find books by metadata. Type an operator followed by a colon and a value – you can combine operators with each other and with regular text search.
missing:cover– books with no cover image. Other fields:publisher,year,isbn,description,rating,review.year:2024– books published in 2024. Use a range for multiple years:year:2020-2024.publisher:Penguin– books whose publisher contains "Penguin" (case-insensitive). Wrap multi-word values in quotes:publisher:"Oxford University Press".source:goodreads– books imported from a specific source. Values:manual,goodreads,calibre,kindle,storygraph,lectr.
Example: missing:cover source:kindle finds all Kindle imports that
have no cover image.
Research tools
Research tools appear in the “Show me” section on every book’s detail page. They open a web search pre-filled with the book’s details. Lectr ships with three defaults – Open Library, WorldCat, and a DuckDuckGo cover image search – and you can add up to five in total.
To configure research tools, open Settings from the Home “…” menu. Each research tool has:
- Search service – DuckDuckGo, Wikipedia, Google, or Custom (enter your own base URL).
- Query template – the search text, with placeholders
{title},{author},{publisher}, and{publication date}that are filled in automatically for each book. - URL suffix – extra parameters appended to the URL after the query. Useful for switching search modes (e.g. images, videos).
URL suffix examples
The URL suffix field accepts raw URL parameters. These are appended after the encoded query. Examples for DuckDuckGo:
&iax=images&ia=images– DuckDuckGo Image search (great for finding cover art or author photos).&iax=videos&ia=videos– DuckDuckGo Video search (find author interviews, book talks, and reviews).
Custom URLs and AI services
Choose Custom as the search service to use any URL. Enter a base URL
ending with the query parameter (e.g. https://example.com/search?q=)
and Lectr will append your query template.
Some AI search services support direct query URLs. For example, you could create a research tool with:
- Perplexity AI – set the search service to Custom, base URL
https://www.perplexity.ai/search?q=, and a query template likeTell me about “{title}” by “{author}”.
Other examples:
- San Francisco Public Library – base URL
https://sfpl.org/search?search=, query template{title} {author}. - AbeBooks – base URL
https://www.abebooks.com/servlet/SearchResults?kn=, query template{title} {author}. - Stockholm Library – base URL
https://biblioteket.stockholm.se/sok?text=, query template{title}+{author}.
Lectr itself does not use AI or send your data to any external service – custom research tools simply open a URL in your browser.
Downloading cover images
When you import books from Goodreads, Calibre, StoryGraph, or Kindle, they may not have cover images yet. To fetch missing covers, open the “…” top menu on the Home screen and tap Download book covers.
Lectr will look up each book by ISBN or title and download any available cover art. A progress bar appears at the top of the Home screen showing how many covers have been processed. Once complete the progress bar disappears and the button shows a green checkmark. Covers are stored on your device so they display offline and sync via iCloud.
Frequently Asked Questions
Can I export my data?
Yes. Tap the “…” top menu on the Home screen and choose Export (CSV). This creates a CSV file containing your full library, notes, quotes, and cross-references that you can share, save, or open in any spreadsheet app. You can also export an individual book with all its notes, quotes, and cross-references from the menu on the book details page.
Can I import books?
Yes. Lectr can import from Goodreads, StoryGraph, Calibre, Kindle (My Clippings.txt), and its own CSV format. See the Importing Data guide for step-by-step instructions and format details.
Does Lectr sync across my devices?
Yes. Lectr uses iCloud to sync your library, notes, quotes, and tags across all your Apple devices signed into the same Apple Account. Sync is enabled by default – as long as you are signed into iCloud, your data will appear on all your devices automatically.
To check or change this, go to Settings > [your name] > iCloud > Apps Using iCloud and look for Lectr in the list. Toggle it off to stop syncing and keep your data on that device only.
If iCloud is disabled or you are not signed in, Lectr works fully offline – your data is stored locally on the device and nothing is lost.
Does Lectr work on Mac?
Yes. On Macs with Apple silicon (M1 or later), Lectr is available as an iPad app and syncs your full library via iCloud. You can find it on the Mac App Store. Barcode scanning works with a built-in camera. The photograph-a-page quote capture is not available on Mac due to camera limitations.
Does the app require an internet connection?
Only for ISBN lookup (fetching book details from an online database) and loading cover images from URLs. Everything else – notes, quotes, tags, ratings, and reading status – works entirely offline.
How do recommendations work if the app is private?
Your book titles, authors, notes, and quotes never leave your device. When you ask for recommendations, the app sends a statistical summary of your reading tastes — themes you return to, how deeply you engage with different topics — not a copy of your bookshelf. The server generates extra candidates and your device filters out books you already own locally, so your library never leaves your device in any form.
There are no accounts. Instead, we use Apple’s App Attest to verify that requests come from a genuine copy of Lectr on a real device, and enforce a monthly quota using a pseudonymous identifier that cannot be linked to you.
Read the full technical explanation →
How many books can Lectr handle?
Lectr has been tested with libraries of 5,000 books, including their associated notes, quotes, and tags.
How does the camera quote capture work?
When adding a quote, tap Photograph Page to take a photo of a book page. Lectr uses Apple's on-device text recognition (Live Text) to extract the words. The text is processed entirely on your device – nothing is sent to a server. You can then edit the extracted text before saving.
What happens if I delete the app?
All data is stored locally on your device. If you delete the app, your library, notes, and quotes will be permanently removed. We recommend exporting your data first if you want to keep a backup.
How do I delete all my data and start fresh?
Go to Settings > General > iPhone Storage, find Lectr in the list, and tap Delete App. This removes the app and all local data. Reinstall from the App Store to start with an empty library.
If you have iCloud sync enabled, your data may reappear after reinstalling. To fully reset, first turn off Lectr in Settings > [your name] > iCloud > Apps Using iCloud, then delete the app. When you reinstall, keep iCloud off until you are ready to sync again.
Data & Privacy
Built for privacy. No accounts, no tracking, no ads.
Troubleshooting
ISBN scan is not recognising the barcode
Make sure you are scanning the ISBN barcode (usually on the back cover, near the bottom). Hold the camera steady and ensure the barcode is well-lit. In low light, tap the flashlight button on the camera preview to illuminate the barcode. If no barcode is detected after a few seconds, a hint will appear with suggestions. You can also type the ISBN manually and tap Lookup.
Book details did not fill in after scanning
Some older or niche books may not be in the online database. If the lookup returns no results, you can enter the details manually on the same form.
Quote text extraction is inaccurate
On-device OCR works best with clearly printed text on a flat, well-lit page. Handwritten text, unusual fonts, or curved pages may reduce accuracy. You can always edit the extracted text before saving.
Contact
For support requests, bug reports, or feature suggestions, please email:
When reporting a technical issue, please include:
- Your device model (e.g. iPhone 15, iPad Air)
- Your iOS version (found in Settings > General > About)
- A description of what happened and what you expected