The new Charge 5 sports a decidedly different aesthetic to its predecessors, dressed in what Fitbit calls its 'Biologic Industrial Design Language.' Supports a selection of proprietary straps.Paired with Fitbit Premium, the Charge 5 also introduces a new metric called Daily Readiness, which uses your health data to create a 'readiness score' giving you an indication of whether you're body is best suited to working out or recovering on a given day. Seven years on from the original entry's debut, the new Charge 5 arrives as the brand's most advanced tracker yet marrying the compact form factor of its predecessors with some of the more premium features and fitness smarts found on the company's smartwatch entries. Fitbit's popular Charge series is one of the most established names and longest-running lines of fitness trackers in the business on the market (and people's wrists) long before many of its rivals even existed.