The Fitbit app will now only work with iOS 15 or higher

Fitbit will no longer support its app on iPhones that do not run iOS 15 or higher. As of March 25, phones that are only capable of running iOS 14 or below – generally, anything older than an iPhone 6 – will no longer work with the Fitbit app once it the app been updated to version 3.77 or newer. 

If you have one of the best iPhones, which tend to be more recent versions, and you’re running an older operating system, you may need to update your device to ensure that you can continue to use the Fitbit app. The best Fitbits. and other devices like them, generally require the latest versions of their companion app in order to operate effectively, and those apps are regularly updated to add new features, fix bugs and so on. 

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