Brain Trainer Special

This app claims to have the largest collection of brain games available, boasting titles like Sudoku, tricky colors, and something called "math ninja." One of these games – similar to games used by other apps – has players memorize phone numbers, which might be a smart way to ready your brain for the real world. "We've learned that people who do engage in these brain fitness exercises do better in the activities that they're engaged in," says Nussbaum. That means that apps featuring tasks that mimic real-life situations will likely do you the most good. [free; Android]