More than 25 years after its birth, “Tetris” is the best-selling mobile game of all time, having surpassed 100 million paid downloads on cellphones around the world. Adam Sussman, vice president of worldwide publishing at Electronic Arts’ mobile unit, said the milestone marked “a huge moment not just for EA but for mobile gaming in general. It speaks to the evergreen appeal of ‘Tetris.'” EA Mobile and the company it licenses the game from, Blue Planet Software, plan to formally announce the milestone on Thursday in Montreal.