Forget biceps—brains are the muscle to train these days. The basis for exercising your mind comes from the concept of plasticity, meaning the brain at any age can modify itself in response to being stimulated. Tech companies have already jumped in with mobile games that promise to enhance your cognitive abilities. But do they work? Although they won’t boost your IQ to genius proportions, some experts agree there is evidence that the right kind of mental stimulation can improve cognitive functions.

“I tell people they have to train and not strain the brain,” says Dr. Gary Small of the Semel Institute for Neuroscience and Human Behavior. “Do things that are fun and engaging—not too difficult, not too easy.” Memory games, he says, help build up fluid intelligence and short-term memory.

Three of the most popular apps—Fit Brains, Lumosity and Elevate—all claim that using them will improve your performance of real-life tasks. Fit Brains (iOS, Android, online) aims to make “dry neuroscientific activity engaging,” says co-founder Mark Baxter. The in-game tasks ask you to match pairs of shapes or identify objects by their shadows, but the basic goal is to develop skills such as hand-eye coordination and reaction speed—handy during your next pickup game of basketball. Lumosity (iOS, Android, online) exercises core cognitive abilities such as memory, attention and pattern recognition, which can help you remember the names of people in a business meeting. Elevate, Apple’s app of the year for 2014 (also available on Android), focuses on communication proficiency with games that improve reading comprehension, grammar and vocabulary. (Know what else does that? Reading a book.) All three apps are free, but premium subscriptions, with prices ranging from $4.99 a month to $100 a year, give you access to more games.

“We’re at a stage where the foundation for brain training is strong,” says Dr. Adam Gazzaley, director of the Neuroscience Imaging Center at the University of California, San Francisco. “But the evidence of what it does, how it works, dosage, side effects—all those details need a lot more research.” Gazzaley believes the complexity of these games can benefit how our brains function, but ultimately the success of brain training depends on collaboration between scientists and game developers. Likewise, as Small points out, not all games are created equal. Many of them are making you better at only one thing—playing the game.