Hi @WayneCC go to either Google Play or the Apple Store and download it free. If you have an existing account, just log on. If you don't have an account, you'll set one up. Once you create an account, you'll need to plug your Fitbit to a charger and follow the prompts. It will tell you which device you have. You don't recall which device you had? If you have an account, it will tell you what you have if you look at your dashboard via the website.
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