Hello @cenglert and welcome to the Community. Absolutely not required. There are some features that require Premium, like the Daily Readiness Score. Premium gives you additional information about some of your data, like more detailed sleep analysis. Many of the workouts and meditations are Premium only. This page has a complete side-by-side comparison.
Laurie | Maryland
Sense 2, Luxe, Aria 2 | iOS | Mac OS
Take a look at the Fitbit help site for further assistance and information.
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