"Hearst Magazines and Yahoo may earn commission or revenue on some items through these links." When 2D puzzles are no longer exciting, 3D brain teasers are the way. These handheld puzzles require ...

A geometry problem over a century old has just found its definitive answer. Mathematicians have confirmed that the solution proposed by Henry Dudeney in 1907 was indeed the most efficient possible.

I'm always on the lookout for a fun and challenging game to play on my phone while I have time to kill. Good Fences is my latest obsession. It reminds me of the board game Blokus and the puzzle ...