En-passant and castling

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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.


Comments

Anonymous said…
Nice app, thank you! Couple suggestions:

1. Use algebraic notation (short form) 1. e5 e5 2. Nf3 Nc6, etc...instead of the long form, as it will save screen space and there really is no need for long form.

2. PGN export or the ability to email the pgn (algebraic short form).

3. Puzzles would be great...
November 20, 2009 at 9:00 PM
Derrick said…
Thanks for the application. I think it's wonderful - one of my favourite apps on my G1. My son and I are using it to learn chess. And thanks for this post - I didn't know about this en-passant thing and thought the app was cheating!
Best regards to you and your family.
January 19, 2010 at 9:15 AM
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