This is Optimizer , a weekly newsletter sent every Friday from Verge senior reviewer Victoria Song that dissects and discusses the latest gizmos and potions that swear they’re going to change your life. Opt in for Optimizer here . A fitness band is for bettering yourself, but casually. It’s lightweight, easy to wear, and not something you have to think too hard about. It’s cheaper than a smartwatch. You get your steps, basic heart rate, and some sleep tracking. Maybe you can see the time, maybe