Lichess

Lichess is a free, open-source chess site, and this is its official Android app, licensed under the GPL. You can play people in real time or by correspondence, join arena tournaments, play bots, solve puzzles, analyse games and follow live broadcasts of major tournaments.

What you can do

The project’s feature list, as F-Droid shows it:

• “play real time or correspondence chess”, arena tournaments and online bots;
• “solve chess puzzles from a wide variety of themes, online or offline”, and race the clock in Puzzle Storm;
• “analyse your games with latest Stockfish locally or on the server”, with a board editor and an opening explorer;
• collaborative studies, a board coordinates trainer, live broadcasts, Lichess TV and streamers;
• “play over the board with a friend” and a chess clock for games on a real board;
• many board themes and piece sets, and an interface “translated into 55 languages”. The Brazilian Portuguese translation is practically complete.

What goes online

F-Droid marks the app TetheredNet, meaning it “relies on lichess.org”: the server addresses are fixed when the app is built, and there is no setting to point it at another server. Online play and the other online features use lichess.org, socket.lichess.org for live games, and lichess1.org for images and downloads; the opening explorer and endgame tablebase use explorer.lichess.org and tablebase.lichess.org. When the network changes, the app checks whether it is online by requesting a small icon from lichess1.org.

This F-Droid build is made from a separate branch that leaves out Google’s Firebase, which the regular build uses for push notifications and crash reports. A Lichess developer put it this way: “The only difference of the fdroid build is that it does not use Google Firebase for push notifications”. Instead it uses UnifiedPush, and F-Droid’s page warns that notifications “are a work in progress and should not be expected to work correctly”; you need a UnifiedPush distributor app, such as Sunup, to receive them. Our scan found no trackers.

Piece sets and sounds

The app’s code is GPL, but it carries all 40 piece sets of the board library it uses, and you can pick any of them in the settings. Their licences come from the Lichess website’s own licence file:

• Free licences (18 sets): cburnett (the default) and merida under the GPLv2+; chessnut (Apache 2.0); letter, pirouetti and pixel (AGPLv3+); mpchess (GPLv3+); fantasy, spatial and celtic (MIT); shapes (CC BY-SA 4.0); kiwen-suwi, firi and totoy (CC BY 4.0); rhosgfx (CC0). Kosal is CC BY 4.0 according to its designer’s repository. Governor and symmetric aren’t listed separately and presumably fall under the projects’ general licences.
• Non-commercial only (16 sets): horsey, california, caliente, maestro, fresca, cardinal, icpieces, gioco, tatiana, staunty, dubrovny, anarcandy, disguised, cooke and monarchy under CC BY-NC-SA 4.0, and xkcd under CC BY-NC-SA 2.5.
• No free licence (6 sets): alpha (“free for personal non commercial use”), chess7, companion and leipzig (each described only as “freeware”), and reillycraig and riohacha, for which no licence is given.
• Sounds: the futuristic, nes, piano and sfx sets are AGPLv3+; lisp is CC BY-NC-SA 4.0; and the default standard set is listed among the website’s non-free files.

The licence for the Lichess logo reads “Only use to refer to lichess.org”. We host the app unchanged, as F-Droid distributes it, and this site has no ads.

About this file

• This is the developer’s own build of version 0.28.4, signed by lichess.org. F-Droid builds the app from source, checks that the result matches, and then publishes the developer-signed file.
• F-Droid publishes a separate file for each processor type; this is the one for 64-bit ARM, which most current phones use. It needs Android 8.0 or later.
• The 69.7 MB file declares 8 permissions, for the network, notifications, vibration and running in the background.
• The screenshots come from the project. We left out one with a tournament banner showing photos of real players.

Flagged by F-Droid:

• NonFreeAssets: Contains non-free assets.
• TetheredNet: Uses a network service run by the developer.

CPU types in this build: arm64-v8a (64-bit ARM, almost every phone since 2017).

Versions currently kept in the F-Droid repository. We host and check only the newest one. Full changelog.