Chess for Android Update

I just released a new version of Chess for Android that, like the previous updates of the other games, improves the text size on larger screens. On the Nexus One, for example, the notation window in previous versions was barely readable. This is now hopefully resolved for all current phones.

Next planned updates consist of adding a small opening book and an option to export a game to some external format.

More Updates

I just released new versions of Checkers and Reversi for Android that improve the text size on larger screens. The reversi application now also uses a randomized opening for variety of play (see below).

Checkers for Android Update

I just released v1.2.2 of Checkers for Android with the following improvements:

+ improved endgame play
+ randomized opening for variety
+ announces win/loss

The latter feature is illustrated in the screenshot below. Please let me know if you encounter any issues with the new features.

Miscellaneous Updates

Just a few unrelated updates.

First, the Android App Review Source website posted a brief online interview with me on developing Android applications.

Also, version 2.01 of BikJump ended at second place in the CCC 17th Amateur Series (Division 8), which opens the possibility of promotion to a higher division. Many thanks to Graham Banks for running this tournament!

Finally, Martin Fierz published Checkers Tutor for Android, a strong checkers program for Android.

Happy New Year!

I just came back from a great trip to my home town Gouda in the Netherlands and want to wish all my blog readers a happy 2010.

En-passant and castling

About once a week, I get an email from a user who claims that Chess for Android makes an illegal move with the pawn or king. Invariably the user is not familiar with en-passant or castling. Therefore, I decided to post a brief summary of these rules.

In the en-passant capture (click for more details), a pawn that just moved two squares can be taken by an opposing pawn as if it only moved one. To perform this move in Chess for Android simply move the pawn as if making the capture, as illustrated below.



The castling move (again, click for more details) involves the king and one of the rooks. The king moves two squares to the left or right while the rook jumps over the king to the adjacent square. The move is only allowed if neither piece has moved before, the path between the pieces is clear, and the king is not in check or crosses a square where it would be in check. To perform castling in Chess for Android, simply move the king two squares to the left or right, as illustrated below.

New Game and Undo

I just posted version 2.1.1 of Chess, Checkers, and Reversi for Android at the Android Market that allows starting a new game or undoing the last played human move while the computer is thinking. In the older versions, this could only happen during the human player's turn. The latest releases remove that unnecessary restriction.

As before, keep in mind that each undo takes back only one half-move (ply). This means that each undo effectively switches the side-to-move. Either use "Switch Side" or make your move on the board to start the engine again.

Status Bar Back!

Although many users seem to like the new full screen, some users really want to see the status bar at all times. Therefore, I just released versions of all my Android games that give the choice between hiding or showing the status bar (in both cases, the screen is still used more efficiently than in the older versions).

This is how a screen without status bar looks.


To enable the toolbar, press the menu button and select "Options".


Then de-select the "Full Screen" option to get the status bar back.

Changing the Board or Pieces

The new release of Chess for Android gives a choice in board style and chess piece sets (others may be added later). To change, press the menu button, which will give you the following screen.


Then, select "Options", which will show you the following choices.


To switch from a wooden board to a more classic board, de-select the "Wooden Board" button. To change piece set, go back to the main menu, then go to "Piece Set" and select one of the sets presented to you. After this, the chess board has a completely different appearance, as illustrated below.



Checkers for Android supports the same choice in board styles.

Android Updates

I just posted v2.0 of Chess, Checkers, and Reversi for Android at the Android Market with the following improvements:

=> Small, normal, and large screen size support.
=> Full screen board layout.
=> On screen buttons moved to menu.
=> Unified trackball cursor.
=> More levels of strength.

In addition, chess has been improved with:

=> Choice of two chess piece sets.
=> Rotating board.