Unlock Android Phone with Fitbit: Step-by-Step

If you have a Fitbit smartwatch and an Android phone, you can set up Smart Unlock so your phone stays unlocked while you’re wearing the watch. This guide walks you through the setup, from pairing to troubleshooting, so you can skip the PIN or pattern when your watch is nearby.

What You’ll Need

An Android phone running Android 5.0 or later (Smart Lock is built into Android).
A Fitbit smartwatch (e.g., Versa, Sense, Ionic) or a Fitbit tracker that supports Smart Unlock (most modern ones do).
The Fitbit app installed on your phone and logged in.
Bluetooth enabled on both devices.
Your phone’s lock screen set to a PIN, pattern, or password (Smart Lock won’t work with Swipe or None).

Step-by-Step

Pair your Fitbit with your phone – Open the Fitbit app, tap your profile icon, and select “Set Up a Device.” Follow the on-screen instructions to pair your watch via Bluetooth. Make sure the watch is charged and near the phone.
Enable Bluetooth on your phone – Go to Settings > Connections (or “Bluetooth”) and ensure Bluetooth is on. Your Fitbit should appear in the paired devices list.
Open Android Smart Lock settings – Go to Settings > Security (or “Lock screen and security”) > Smart Lock. On some phones, it’s under Settings > Security & location > Smart Lock. If you don’t see it, search “Smart Lock” in the Settings app.
Enter your PIN/pattern/password – When prompted, enter your current lock screen credential to access Smart Lock options.
Select “Trusted devices” – Tap “Trusted devices” (sometimes called “Trusted devices” or “Smart Lock” > “Trusted devices”).
Add your Fitbit – Tap “Add trusted device.” Your phone will scan for nearby Bluetooth devices. Select your Fitbit from the list. If you don’t see it, make sure the watch is awake and close to the phone.
Confirm the pairing – A confirmation dialog may appear on your phone; tap “Yes” or “OK.” If your watch shows a pairing prompt, accept it.
Test it – Lock your phone (press the power button), then wake it while wearing the watch. It should unlock without asking for your PIN. If it still asks, check the troubleshooting section below.

Common Mistakes

Using an unsupported lock screen – Smart Lock requires a secure lock (PIN, pattern, or password). If you use “Swipe” or “None,” Smart Lock won’t appear in settings.
Bluetooth off or not connected – If Bluetooth is off, or the watch is not connected, Smart Lock won’t work. Check the Bluetooth icon in your notification bar.
Watch battery low – Some watches disable Bluetooth when battery is critical. Charge it above 20%.
Adding the wrong device – Make sure you select the Fitbit, not your car’s Bluetooth or earbuds. The device name often includes “Fitbit” or the model name.
Not entering your PIN when prompted – You must enter your lock screen credential to enable Smart Lock. If you skip it, the option won’t activate.

Tips

Keep the watch on your wrist – Smart Lock uses the watch’s proximity and connection. If you take it off, the phone will lock again after a few minutes.
Use a strong PIN – Since Smart Lock bypasses it when the watch is near, a 6-digit PIN is safer than a 4-digit one.
Update both devices – Keep your Fitbit firmware and the Fitbit app updated. Android updates can also affect Smart Lock behavior.
Check “Trusted devices” list – If you have multiple trusted devices, ensure your Fitbit is not accidentally removed.
Use “On-body detection” as a backup – If you don’t want to rely solely on the watch, enable “On-body detection” in Smart Lock so the phone stays unlocked while you’re carrying it.

Troubleshooting

My Fitbit doesn’t appear in the list of trusted devices. Make sure the watch is connected in the Fitbit app (open the app and check the device status). Restart both devices: turn off Bluetooth on the phone, then turn it back on. Also, put the watch in “wake” mode (raise your wrist) so it’s actively broadcasting.

Smart Lock option is missing from Settings. This can happen on some Android skins (e.g., Samsung, Xiaomi) where the option is renamed or hidden. Search “Smart Lock” in the Settings search bar. If it’s still not there, your phone may not support it (rare on Android 5+). Check for a “Trusted devices” option under “Biometrics and security.”

Phone still asks for PIN even with the watch on. First, confirm the watch is connected (check the Fitbit app). Then, remove the trusted device and re-add it. Also, check if your phone’s “Smart Lock” is turned off entirely. Sometimes a security update resets it.

Smart Lock works but stops after a few hours. This is often due to the watch disconnecting for a while (e.g., when you take it off to charge). Re-add the device or ensure the watch stays connected. Also, check that the Fitbit app isn’t being killed by battery optimization – go to Settings > Apps > Fitbit > Battery and set to “Unrestricted.”

I get a “Couldn’t add device” error. This usually means the Bluetooth pairing is incomplete. Forget the Fitbit in Bluetooth settings, then re-pair through the Fitbit app. Also, make sure no other device is trying to connect to the watch simultaneously.

Frequently Asked Questions

Does Smart Unlock work with any Fitbit? Most Fitbit smartwatches and trackers with Bluetooth support it, but older models may not. Check the Fitbit app’s device settings for “Smart Unlock” or refer to the manufacturer’s support page.

Can I use Smart Unlock with a Fitbit without the app? No, the Fitbit app is required for initial pairing and to maintain the connection. The watch must be connected to the phone via Bluetooth, which the app manages.

Will my phone unlock if I’m wearing the watch but it’s not on my wrist? No, Smart Lock relies on the Bluetooth connection. If the watch is not on your wrist (e.g., in a bag), it may still work if it’s close enough, but it’s designed to detect the watch being worn. For better security, use “On-body detection” as well.

Is this the same as “Smart Lock” on Android? Yes, Fitbit Smart Unlock uses Android’s built-in Smart Lock feature. The watch is simply added as a trusted device.

Does Smart Unlock drain my battery? It can slightly increase battery usage on both devices because Bluetooth stays active. However, modern Bluetooth is efficient, and the impact is usually minimal. If you notice significant drain, check the Fitbit app’s battery usage in Android settings.

Can I remove the Fitbit as a trusted device later? Yes, go to Settings > Security > Smart Lock > Trusted devices, tap the Fitbit, and select “Remove.” You’ll need to enter your PIN to make changes.

General steps for current mainstream versions; menus can differ by device and version. See the disclaimer or report an error.

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