Fashion fuses with technology in the new Ralph Lauren (ralphlauren.com) PoloTech shirt ($295). Developed with the Montreal-based high-tech apparel company OMsignal, the smart shirt is designed to guide a better workout by reading biometric data through a rechargeable Bluetooth-enabled black box and live streaming that information to the PoloTech app, which is available on the iPhone or Apple Watch. The unit snaps onto the shirt near the wearer’s heart and reads g-force measurements through a built-in accelerometer and gyroscope. It also gathers data through the silver fibers woven throughout the snug-fitting shirt’s fabric—a breathable blend of polyester, nylon, and spandex. The app analyzes heart rate, respiration depth, energy output, calories burned, and steps taken, and offers customized cardio, strength, and agility workouts for optimal performance.