Most true wireless models work with a companion app that helps connect the earphones to your phone. Plenty of apps beef up their appearance by duplicating the controls you already get on the physical earpieces. This can add some convenience, but it doesn't add a layer of control. Other apps offer the ability to make tweaks to certain settings. For instance, you might be able to assign your phone's voice assistant to a shortcut button and adjust the automatic playback behavior for when you insert or remove the earphones. Aside from potentially crucial firmware updates, one of the best things an app can do is enhance the listening experience with an adjustable EQ. Not all apps have an EQ, but allowing you to tweak the bass or treble to your taste is a huge plus—and apps that have customizable presets are increasingly common. A few manufacturers don't use a companion app at all, including Apple. Though you can argue that this makes the overall experience easier and more streamlined, we like the additional control an app provides. We include a rundown of companion apps and how they work in each of our reviews. Finally, if you're still looking for the perfect pair of earphones and are willing to increase your budget, check out our picks for the best true wireless earbuds overall.