Set Up Your Fitbit on an iPhone
2. Tap Join Fitbit. If you don't already have an account, create one (it's free) by entering your email address and a password.
3. Choose your Fitbit device.
4. Tap Set Up at the bottom of the screen.
5. Create an account, and input your personal information. The app will guide you through entering your height, gender and weight.
6. Pair your Fitbit with your iPhone. Make sure Bluetooth is enabled on your iPhone. The app will automatically search for your tracker. If you have a Fitbit Charge 2, a series of numbers will appear on your tracker's screen, which you'll type into your phone to complete the pairing.