Chess#

[bretti]

http://itunes.apple.com/us/app/chess/id427474295?mt=8

Once we have a look at CHESS# it seems that it simple shows a Shredder-like GUI with a well known engine (Stockfish?). http://www.talkchess.com/forum/viewtopi ... t&start=40


A closer look shows differences between known engines and CHESS#:
It is not possible to use the book "obook.bin" within Stockfish and CHESS# cannot use the Stockfish-book "guibook.bin". The App itself is 1MB, the whole installation is about 19MB (book: 15MB). The installed files contains a "TODO" with a hint about the engine: "The core chess engine is based on Crafty, that finished 4th at the World Microcomputer Chess Championship. SSMD heavily optimized this engine to fit iPhone´s and iPad´s ARM architecture. The resulting Elo peak of 2800 on iPhone 4 is the highest rating available on mobile devices. Additional modifications were done to simulate human mistakes on lower Elo levels."

At the App Store you can read: "This high professional chess application is based on 'Pinkbird ARM', a brand new chess engine optimized for iPhone's and iPad's ARM architecture. It has a peak Elo rating of 2900 on iPhone 4 which is actually the highest available rating on mobile devices.
Chess# currently limits the 'Pinkbird ARM' engine to its playing strength on an iPod Touch 1G which is 2600 Elo. This limitation is subject to change in future versions."

Another file of the installation is interesting: "matches" shows the results between CHESS # and Shredder on different Elo-levels so it seems to be clear that Shredder was used to train and tune CHESS # and its Elo-levels.

So it could be indeed a new strong engine, that means an engine that is not used in any other Chess App for iOS yet. I think the engine is stronger than Shredder but not as strong as Hiarcs or Stockfish. It is possible that the engine is based on Firebird or Robbolito ("Pinkbird"?!).


But the GUI is not impressive:
- no evaluation at all!
- main line only 5 halfmoves (after two taps)
- no opening-informations
- engines clock is not shown
- no analyse-mode
- bug from elo level 1800 to 2600: engine freezes 4 or 2 halfmoves before checkmate

[stevenaaus]

The interface looks great, expecially considering the screen size.

- bug from elo level 1800 to 2600: engine freezes 4 or 2 halfmoves before checkmate

That's a big bug.

[mephisto]

Many thanks Stefan
I did try to contact the developer about the engine but they did not reply.
Bryan

[kinderchocolate]

I had installed it a few while ago. It wasn't bad, but I don't like the interface that much. I especially hate when I make a move, the notation of the files and ranks pop up, I don't need to see where e4 is to make a move from e2 to e4.

It is designed for casual players, not quite suitable for talkchess hardcores. Comparing with other free downloads, this is one of the best.

[mclane]

it looks the engine has permanent brain. some moves it does in an instant although time control is 40/120. could be stockfish. at least the moves are often similar like stockfish moves.

[bretti]

it looks the engine has permanent brain. some moves it does in an instant although time control is 40/120. could be stockfish. at least the moves are often similar like stockfish moves.

I am sure it is not Stockfish:

• - The books are not compatible so one would have changed it only to use another book?
  - The app itselfs is 1 MB, the Stockfish app is 1,7 MB.
  - I have never seen a mate-bug like that (between Elo 1800 and 2600) in Stockfish or Glaurung (Chess# cannot checkmate, it freezes at the last one or two moves with each site!).
  - And why should the TODO-file names "Crafty" instead of Stockfish?
  - The "matches"-file shows tests for the Elo-levels against Shredder. It would not be necessary for Stockfish which already has Elo-levels.

[aturri]

(...) The installed files contains a "TODO" with a hint about the engine: "The core chess engine is based on Crafty, that finished 4th at the World Microcomputer Chess Championship. (...)

Well, I wonder what does the author mean with "based on Crafty", and what does Bob think about it

Did he take source code blocks, or has just read, understood and write from scratch a new engine? (hard to belive) Does it includes the source code? Crafty's license is very clear about copying and making commercial use of his work, opposite to Stockfish, e.g.

Hope it was not another Rybka/Vas case...