Admittedly, Ubuntu still has problems and one of these is with its Software Center application which is Ubuntu's version of an App Store. It is slow and buggy to the point of being unusable. Fortunately there is an alternative with the tried and true Synaptic Package Manager; it's not flashy and offers only free software, but it works.
I mention this because I don't want newcomers to Ubuntu to be turned off by what should be a bug-free program. Use the Synaptic Package Manager and search for terms like chess, pgn, and xboard. You'll find plenty of free stuff (including crafty, fruit, glaurung, gnuchess, sjeng, stockfish, and toga) which will install without a problem.
ranking lists - Why windows
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