Random musings from Acid Ape Studios
In particular about Acid Ape Chess

December 23, 2022 Acid Ape Chess 1.11 released

Acid Ape Chess 1.11 has been released:

  • In two-player games, it is now possible to use the DGT3000 as time source (by selecting an option other than 25). Depending on your physical board model, this may reduce and/or mask clock lag, improving the players experience (particularly in blitz games).
  • The PGN parser has been made more tolerant: PGN headers are no longer required for the first game (for instance, 1. e4 is now considered valid PGN data). This is useful for pasting moves with Main menu > Game > Paste PGN from clipboard.
  • Arasan has been updated to 23.4.
  • Miscellaneous fixes and improvements.
December 18, 2022 Chess Engines Collection 1.7 released

Chess Engines Collection 1.7 has been released:

  • Stockfish has been updated to version 15.1.
  • Lc0 has been updated to version 0.29.0.
May 23, 2022 Acid Ape Chess 1.10 released

Acid Ape Chess 1.10 has been released:

  • Engines can now use custom data files. This is useful for using a custom neural network with engines such as Arasan, Stockfish or Lc0. For instance, to use a custom NNUE file with Stockfish:
    • open the engine settings dialog
    • scroll down to the EvalFile option
    • click the open button at the right of the text entry
    • select the .nnue file of your choice in the Android file picker
  • A node limit can now be specified in the engine settings dialog. This uses the UCI go nodes command.
    Maia tip: by default, the Maia we ship in Chess Engines Collection internally sets its node limit to 1 (as per the Maia website instructions), which makes it deterministic. To make it non-deterministic and slightly more challenging, set its node limit to a small value such as 50.
  • The Play dialog now features a recent games list. To access it, press the button at the right of the blindfold button. Moreover, the logic which determines and remembers default values has been improved.
  • Arasan has been updated to 23.3.
  • Miscellaneous fixes and improvements.
May 18, 2022 Chess Engines Collection 1.6 released

Chess Engines Collection 1.6 has been released:

  • Stockfish has been updated to version 15.
  • Lc0 has been added (with the upcoming Acid Ape Chess 1.10, you will be able to use custom neural networks).
  • Bad Gyal has been added. Bad Gyal is a Lc0 network trained on human games and enhanced by low depth Stockfish searches.
  • A upstream Rodent III bug which caused it to always play the same opening has been fixed.
November 22, 2021 Acid Ape Chess 1.9 released

Acid Ape Chess 1.9 has been released:

  • OTP mode (over the phone) has been added: two players can now play against each other on the same phone or tablet, each on their own virtual chessboard. OTP mode can also be a useful visualization when two players are playing on a physical board. To enable OTP mode, create a two-player game by using Position > Play in the main menu, then press the OTP MODE button of the game information subpage.
  • Open Exchange 2.0 is now supported (this restores the ability to run several third-party chess engine packages on Android 10 and later).
  • Evaluation graph changes:
    • The data is now cached. This allows to toggle the graph without having to recompute the plots.
    • The data can now be precomputed in the background while playing a game. This allows the graph plots to be available shortly after a game ends (precomputation can be enabled by pressing the settings button at the right of the graph).
    • The score indicator now displays whether the current position is a claimable draw.
  • Now handles automatic draws by fivefold repetition and by seventy-five-move rule (as per the updated FIDE Laws of Chess).
  • Draw offers are now recorded in the move list, using the standard FIDE Laws of Chess notation (=).
  • New piece theme: Go (useful for semi-blindfold).
  • A protocol change in the third-party EGTB service broke EGTB support: fixed.
  • Arasan has been updated to 23.0.1.
  • Miscellaneous fixes and improvements.
September 10, 2021 Chess Engines Collection 1.5 released

Chess Engines Collection 1.5 has been released:

  • Stockfish has been updated to version 14.
  • Maia has been added. Maia is a human-like neural network chess engine trained on millions of human games. It is powered by Lc0.
April 16, 2021 Acid Ape Chess 1.8 released

Acid Ape Chess 1.8 has been released:

  • In order to adhere to FIDE/USCF rules and to be consistent with the DGT3000, clock increments are now added to the initial game time. For example, Acid Ape Chess would previously start a 3+2 game with clocks at 3:00; it now starts such a game with clocks at 3:02 (except for online games, because chess servers do not use these rules).
  • A problem which would affect Goi.bin and a few other PolyGlot opening books has been fixed.
  • The orientation of the DGT board is now auto-detected, i.e. you can now place the black pieces on the white side. This is especially useful for boards which do not have coordinates.
  • When challenging a player, you can now select an advanced time control. This allows you to go beyond the 99 minutes limit of the simple time selector.
  • The standalone clock app now supports advanced time controls.
  • Because of Google Play restrictions which took effect in November 2020, Acid Ape Chess is no longer able to run custom or Open Exchange chess engines on Android 10 and later. To be compatible with Acid Ape Chess on Android 10 and later, a third-party engine must now be published as an Android app and use ACEI (Ape Chess Engine Interface).
  • Arasan has been updated to 22.2.
  • Miscellaneous fixes and improvements.
October 29, 2020 Acid Ape Chess 1.7 released

Acid Ape Chess 1.7 has been released:

  • Custom opening books are now supported: PolyGlot (.bin) and Arena (.abk).
  • Engines can now be cloned (useful for having an engine duel itself with different settings).
  • The evaluation graph has been improved.
  • DGT move detection has been improved.
  • Arasan has been updated to 22.1.
  • A few minor issues have been fixed.
September 7, 2020 Chess Engines Collection 1.4 released

Chess Engines Collection 1.4 has been released:

  • Stockfish has been updated to version 12.
  • Open Exchange will no longer work when Google Play will require apps to target at least Android 10. To be ready for this upcoming requirement, we have replaced Open Exchange by ACEI (Ape Chess Engine Interface).
  • A few upstream Rodent III bugs have been fixed.
June 11, 2020 Acid Ape Chess 1.6 released

Acid Ape Chess 1.6 has been released:

  • Multiple engine best moves (aka MultiPv) can now be displayed (increase the Principal variations setting).
  • Analysis can now be paused (long-press the stop analysis toolbar button).
  • A Samsung bug affecting the main menu button has been worked around.
  • Is compatible with the upcoming version of Chess Engines Collection.
  • A few minor issues have been fixed.
May 20, 2020 Acid Ape Chess 1.5 released

Acid Ape Chess 1.5 has been released:

Lichess changes

  • Challenges are now supported (in and out).
  • Friends are now supported.
  • Ultra Bullet games can now be played (¼-, ½-, and ¾- minute).
  • Acid Ape Chess no longer prompts for resuming correspondence games on login (Lichess supports playing normal games and correspondence games simultaneously).
  • Resuming games now works properly.
  • A Lichess protocol change caused Acid Ape Chess to no longer receive chat messages from the opponent: fixed.

Other changes

  • An evaluation graph has been added.
  • FICS friends are now supported.
  • The game information subpage now displays local PGN duel statistics (for human duels and engine duels).
  • To be compatible with the upcoming Android 11, PGN files are now saved in the app-specific storage area. Games from a previous installation of Acid Ape Chess will be automatically copied to this location on first startup. An import/export feature has also been added to the PGN Explorer.
  • The system file picker is now used when adding a custom engine and when importing a puzzle collection (required by the upcoming Android 11).
  • When using a DGT board, red exclamation marks would sometimes be displayed during castles: fixed.
  • The Select Option 25 on your DGT3000 message is no longer displayed for the DGT Revelation II.
  • Arasan has been updated to 22.0.
  • Performance has been improved.
  • A few minor issues have been fixed.
November 28, 2019 Online user manual

The Acid Ape Chess User Manual is now available on our website (singlepage HTML).

PDF and multipage HTML versions may be released in the future.

November 25, 2019 Acid Ape Chess 1.4.1 released

Acid Ape Chess 1.4.1 has been released:

  • Arasan has been updated to 21.4.
  • A few minor issues have been fixed.
May 7, 2019 Acid Ape Chess 1.4 released

Acid Ape Chess 1.4 has been released.

New in this release:

  • Favorites support has been added to the OTB player list.
  • The OTB player list can now be filtered by sex.
  • The OTB player search has been made smarter. For instance, simply type v anand to easily reach Viswanathan Anand.
  • The auto-annotation algorithm has been improved.
  • Specific Lichess users can now be searched (Main Menu > Players > Lichess > Search for more).
  • The Komodo-specific "Skill" UCI setting is now supported natively by Acid Ape Chess. This setting was introduced in Komodo 11.
  • The rankings page now features an OTB tab, listing the FIDE world rankings.
  • Arasan has been updated to 21.3.
April 10, 2019 Acid Ape Chess 1.3 released

Acid Ape Chess 1.3 has been released.

New in this release:

  • An eval gauge is now displayed next to the board during analysis or engine play; this gauge can be turned off in the settings page.
  • A link to our privacy policy has been added (Main Menu > Settings and help > Privacy policy).
March 29, 2019 Congratulations!
When choices are to be made...

Congratulations to Mohammad Fahad Rahman for his stellar performance at the Asian Zonal Chess Championships 2019, finishing ahead of several adult Grandmasters to claim the title! This achievement instantly made him an IM and qualified him for the FIDE Chess World Cup 2019.

Needless to say, Mohammad is using Acid Ape Chess Grandmaster Edition for his game preparation and analysis. His next goal is to become a Grandmaster, and we have decided to support him in that quest. By purchasing Acid Ape Chess Grandmaster Edition, you help young talents such as Mohammad.

March 19, 2019 Acid Ape Chess 1.2 released

Acid Ape Chess 1.2 has been released.

Highlights from this release:

  • Games can now be auto-annotated (using a chess engine and the endgame tablebases).
  • Game subpage layouts can now be saved and restored (long-press a game subpage title to access the subpages layout selection dialog).
  • Engine evaluation scores can now be displayed as absolute values (positive when white is winning, zero when sides are equal, negative when black is winning) by disabling the Display relative score in the global settings page.
  • Some annotated moves (!, !!, ?, ??) are now colored in green, light green, red or light red.
  • The DGT3000 sounds can now be toggled.
  • The move speech recognition algorithm has been slightly improved.

Auto annotation in action, using the game 10 of World Chess Championship 2018:

Auto annotation, step 1 Auto annotation, step 2 Auto annotation, step 3 Auto annotation, step 4

As can be seen in the last screenshot, Stockfish 10 believes that Fabi could have won this game, as he had a quite favorable eval when the draw was agreed.

March 12, 2019 Acid Ape Chess 1.1 released

Acid Ape Chess 1.1 has been released.

Highlights from this release:

  • Physical board support: a stabletime algorithm (similar to the one in the DGT Rabbit Plugin) has been implemented; this eliminates incorrect detection of sliding moves on sensitive boards.
  • Time control support has been greatly extended. A wide range of predefined time controls is now provided. You can also add custom time controls supporting multiple periods, move limits and Fischer increments.
  • Engine and two-player games can now be adjourned and resumed later on.
  • The flipped and clock at left physical board page settings are now saved permanently.
  • Acid Ape Studios notifications (if any) are now periodically retrieved from our server and shown as Android system notifications (you can disable this notification channel in the Android system settings).
  • Physical board support: kings can now be placed in two of the center squares to encode the game result.
  • Physical clock support: opponent moves are now displayed on the physical clock.

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