<blockquote>“Nigalidze would promptly reply to my moves and then literally run to the toilet,” Armenian grandmaster Tigran Petrosian <a href="http://www.telegraph.co.uk/culture/chess/11531055/Grandmaster-makes-bad-move-after-being-caught-cheating-at-chess-in-a-lavatory.html" target="_blank">said</a>. “I noticed that he would always visit the same toilet partition, which was strange, since two other partitions weren’t occupied.”

Petrosian complained to the officials. After Nigalidze left the bathroom once more, officials inspected the interior and say they found an iPhone wrapped in toilet paper and hidden behind the toilet.</blockquote>
via <a href="http://www.washingtonpost.com/news/morning-mix/wp/2015/04/14/chess-grandmaster-caught-using-iphone-to-cheat-during-international-tournament/">Chess grandmaster accused of using iPhone to cheat during international tournament - The Washington Post</a>.