OpenBook

Changelog

Last updated 29 August 2026

User-visible changes, newest first. Bugs or requests: feedback@openbookchess.com.

Choose what you practice 29 August 2026

• New Practice pool screen (menu → Practice pool): every line in a repertoire, showing what’s in your practice rotation and what’s still waiting (note: this only matters if you import lines — adding lines through Build mode automatically puts them into the practice pool, unless you’ve chosen the manual option below). Tap any line, or a whole opening, to add it or take it out of the pool.
• Taking out an opening you’ve already practiced keeps its progress — put it back later and it picks up where it left off instead of starting over. This doesn’t delete the line from your repertoire, it just pulls it out of the practice pool.
• New lines per day now has a manual option: nothing enters your rotation on its own and you choose openings yourself. Importing a repertoire asks which you’d prefer, and you can change it any time from the Practice pool.

Much faster startup for large repertoires 28 August 2026

• OpenBook used to re-analyze your entire repertoire every time you opened it, which can take a long time if you have thousands of positions saved. It now remembers the work between visits, so opening the app should be quick, even with thousands of positions saved.

Practice by likelihood, and both databases at once 22 August 2026

• Practice → “Most likely first” drills every line for that color in order of how frequently you are expected to face it (user request). I’ll be interested in your feedback on this feature and whether it feels accurate, as the math could be done in a few ways for this.
• In Build, you’ve always been able to toggle between the database for your rating and for the masters. Now there’s an option to show both, which puts the masters game count in parentheses after the games in your rating (user request).

Analysis links, a quieter practice board, and a clearer Map 22 August 2026

• “Analyze this position” opens the current position (from Build or Practice) straight into an analysis board on Lichess or Chess.com (user request).
• Menu → Settings → Evaluation bar in practice turns the evaluation bar off while you review. If there are tactics in your opening prep, the bar jumping can spoil it in practice mode (user request).
• If you have a bunch of lines in one opening, they now split into variations in Map (user request).

Mobile build mode UI revision 14 August 2026

• The move database now sits just below the board on phones (user request). Other elements rearranged to make room. Reminder, if you want more room on your screen, add OpenBook to your Home Screen (Share → Add to Home Screen on iOS, or Install on Android), then you will have the full phone screen without the browser UI elements taking up space.

Click any move to jump there 13 August 2026

• The moves of your current line now appear above the explorer in Build mode. Click or tap any move to jump straight to that position (user request).

Resize board 13 August 2026

• Drag the divider between the board and the panel (works on both mobile and desktop views) (user request).

Map looks a bit friendlier for new users 13 August 2026

• Red used to mean “short review interval”, which included every line you’d just learned, so a brand-new repertoire opened to a wall of red. New lines now start as yellow, and the red is reserved for the lines you missed on your last review (user feedback).

The Map: see your whole repertoire at a glance 29 July 2026

• A new Map tab next to Build and Practice shows every line you've saved as one cell, colored by how well you know it — fragile to solid — and grouped by opening. Hollow cells are lines that have slipped overdue; a ✓ means you've already practiced that line today.
• Tap any cell for the line's details and one-tap Practice. Every opening has Practice weakest, which drills its shakiest lines first and skips anything you've already done today.
• The ⋯ next to an opening runs your repertoire checks on just those lines: find popular opponent moves you haven't answered, or have Stockfish look for weak moves — scoped to the opening, so it's fast.
• A progress chart tracks how many of your lines are solid over time.

Optional reminders 24 July 2026

• Menu → Reminders → Show lines due on the app icon: the number of lines waiting appears on the icon of your installed app. No notifications — this option never sends you one.
• Menu → Reminders → Remind me daily: one notification a day when you have lines due, at your local evening. Never more than one, nothing at all on days you've already practiced, and it's what keeps the icon count current while the app is closed.
• Both are off by default and each can be turned off from the same menu. On iPhone, both need OpenBook added to your home screen first — that's an Apple restriction on web apps.

Practice has a finish line 24 July 2026

• Importing a course used to drop thousands of lines into your practice queue at once, all due immediately, with no way to reach the end of it. Now OpenBook introduces a set number of new lines per day — 20 by default, changeable in menu → Settings, or turn the limit off entirely.
• Lines that are due for review are never held back. The limit only applies to lines you've never practiced.
• Finish the day's new lines and OpenBook tells you so, and how many are waiting for tomorrow. Want to keep going anyway? Keep practicing does, and it counts.
• After importing a PGN or a Lichess study, OpenBook now offers to start reviewing it straight away.

Import Lichess studies right from the app 22 July 2026

• Menu → Import → Study: browse your Lichess studies, pick the chapters you want, and import — no downloading and re-uploading a PGN file (user request). Pasting a study link works too.

Notes travel with your PGNs 22 July 2026

• PGN export now includes your position notes as standard comments, and PGN import reads them — bring in an annotated Lichess study and its comments become notes on the right positions.
• If an imported note differs from one you already wrote, you review them side by side and choose which to keep. Nothing is overwritten silently.

Add a whole line at once 22 July 2026

• Browse past your prep and one tap saves every new move (user request); if an add creates a fork at a position you'd already prepared, a note takes you there to review.

Install OpenBook on your phone 22 July 2026

• Add it to your home screen (Android offers one-tap install; iPhone via Safari's Share menu) and it opens full screen like an app.
• Heavy assets like the analysis engine are cached after your first visit, and your board and repertoire keep working even offline.

Game review 21 July 2026

• New repertoire check: fetch your recent Lichess and Chess.com games and see where each one left your prep — prepared moves you mixed up, and opponent replies you hadn't covered.
• Repeat offenders group together and rise to the top; click a result to jump to the position and fix it.
• Standard chess only, bullet optional, up to 100 games per site. Runs entirely in your browser — your games and usernames never touch our servers, and it works for guests.

Bigger repertoires 21 July 2026

• You can now save up to 40,000 positions (20,000 for each color) — four times the old limit.

Guest mode 21 July 2026

• Use all of OpenBook without an account. Guest work is stored in your browser.
• Sign in later and OpenBook offers to merge your guest work into your account.
• Privacy policy updated to cover guest mode.

Weak-move finder 5 July 2026

• New repertoire check: Stockfish scans your prepared moves and flags ones that lose ground, ranked by how often you'd face the position. Runs in your browser.
• Click a result to jump to the position and fix it.

Practice sets 4 July 2026

• Save part of your repertoire — your anti-Sicilian lines, say — as a named set and practice just those lines.
• Sets are anchored to a position, so new lines through it join automatically.
• Practicing a set early doesn't inflate your review intervals; misses still count.

Mobile fixes 30 June 2026

• Fixed the opening database disappearing in landscape on phones, plus layout on short screens and hover states on touch devices.

Explorer readability 28 June 2026

• Move rows show a popularity bar alongside win/draw/loss (user request).
• Masters picks (★) and engine picks (◆) use distinct shapes, with tooltips (user request).
• Cleaner board arrows and better board centering on phones.
• Fixed: replaying a line with the keyboard offers "add to repertoire" again (user report).

Speed 27 June 2026

• Repertoire edits are instant, and likely next positions are prefetched.
• The eval bar now shows in both Build and Practice.
• Practice starts with the color you've practiced least recently, instead of always White.

Engine and PGN 25 May 2026

• Stockfish runs in your browser: eval bar and best-move markers in Build mode (user request).
• PGN import and export, so you can bring an existing repertoire or take yours elsewhere (user request).
• The Practice tab shows how many lines are due.

Public launch 23 May 2026

• OpenBook opens at openbookchess.com.

Alternate lines 22 May 2026

• A position can hold more than one prepared move; practice drills each branch as its own line.
• Redesigned mobile controls under the board.

Onboarding 21 May 2026

• Tutorial for new users, a rating prompt, account deletion, and the privacy policy and terms pages.

Gap finder 20 May 2026

• New repertoire check: find popular opponent moves you have no answer to, ranked by how likely you are to face them.
• Rating setting — the opening database shows games from players near your level.
• Deleted lines go to a restorable trash. Visual redesign.

Rename to OpenBook 19 May 2026

• Lichess sign-in, opening-data caching, and ★ markers for master-approved moves, in preparation for public release.

First version April 2026

• Built as the developer's personal opening trainer: a board, the Lichess opening database, and spaced-repetition practice.