Fitbit app version 4.50 added an in-app dark theme for Android and iOS, with options to follow your phone’s appearance or choose Light or Dark yourself. The update began rolling out in late August 2025, but availability was staged, and Fitbit cautioned that some interface elements might not display correctly in dark mode at launch.
What Fitbit app version 4.50 changes
Version 4.50 is a mobile-app update, not firmware for a Fitbit watch or tracker. Its headline feature is a Theme setting that lets you change the Fitbit app’s appearance. Fitbit also listed bug fixes and performance improvements without specifying them individually in its Android release notes.
Fitbit announced dark mode on August 20, 2025. 9to5Google reported the broader rollout on August 27, and Fitbit’s Android release-note post was dated August 28. These dates describe a rollout, not a single day on which every user received the update. The theme was also separate from the broader Fitbit redesign associated with Google’s Material 3 Expressive work, as 9to5Google reported.
How to turn on Fitbit dark mode
Fitbit’s release information gives this settings path; labels can vary slightly by platform or localization:
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- Update Fitbit to version 4.50 or later through Google Play or Apple’s App Store.
- Open the Fitbit app and open Profile.
- Select Fitbit Settings, then tap Theme.
- Choose Dark, Light, or System default.
With System default, Fitbit follows the phone’s light or dark appearance. Choose Dark or Light to keep Fitbit in that appearance regardless of the phone’s setting. Fitbit describes the choices in its dark-mode announcement.
Phone requirements for the 4.50 release
Fitbit’s release information specified Android 11 or later for Android and iOS 16.4 or later for iPhone. These are the requirements reported for version 4.50 in August 2025, not necessarily the requirements for the Fitbit app today. The platform details appear in Fitbit’s release information.
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If the update or Theme option is missing
A missing update does not by itself show that your phone is incompatible: Fitbit users reported that availability arrived at different times. Try these checks in order. These are standard troubleshooting steps, not guaranteed fixes documented by Fitbit.
- Check the installed Fitbit version in Google Play or the App Store, and install an update if one is offered.
- After updating, fully close and reopen Fitbit. If the setting is still absent, restart the phone and check again.
- Confirm you are using the current Fitbit mobile app and meet the operating-system requirement reported for 4.50.
- If the store still offers an older build, wait and check the official store again; rollout timing can vary. Avoid sideloading an APK as a workaround.
Fitbit Community discussion of the iOS rollout reflects the staggered availability, but does not establish one fix for every case.
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Not every screen was guaranteed to look right
Fitbit said most of the app would support dark mode, while warning that a limited number of elements might not render correctly at launch. Users in the iOS discussion described some food-logging and watch-related areas remaining light or having readability problems. Those are anecdotal examples, not evidence that every user will see the same issue. Fitbit’s announcement does not promise a completely dark appearance across every app screen or device-management view.
The change is visual; Fitbit did not describe it as an update to tracking, syncing, or health metrics. Its announcement mentioned potential battery benefits on OLED displays, but supplied no Fitbit 4.50 battery measurements, so savings should not be assumed for every phone.
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