Lezyne’s Mega XL GPS is your activity-tracking app on steroids—a lot of steroids. It has every feature you can imagine, from smartphone synchronization to downloadable routes for offline navigation. The battery packs plenty of punch, with 48 hours of run time, and the included swivel mounts vertically or horizontally on your bike’s handlebars. Familiarize yourself with the menu’s options before heading out—it takes some getting used to. $200; lezyne.com.