Currently, you cannot use any official SDK, including SDK5, to target the Fitbit Versa 4 for developing third-party apps or clock faces. The Fitbit Versa 4 does not support third-party apps or custom clock faces due to the lack of an official SDK for this device. The Versa 4, along with the Sense 2, does not have a publicly available development kit, which is necessary for creating and testing custom content on these devices.
The Fitbit Versa 3 SDK is not compatible with the Versa 4, and each watch requires its own specific development kit. For the Versa 3, the SDK is well-documented and supported, allowing developers to create and publish apps and clock faces. However, for the Versa 4, there is no official SDK or simulator available, making it impossible to develop or test custom content using standard development tools[1][3][9].
Some users have attempted to use pre-release SDK versions or modify existing projects to target the Versa 4, but these efforts are not officially supported and often result in compatibility issues or crashes[3]. The best approach for developers interested in creating content for Fitbit devices is to focus on models like the Versa 3, which have a well-supported SDK and development environment[9].
Fitbit has not announced plans to release an SDK for the Versa 4 or Sense 2, which limits the potential for third-party development on these devices[10]. Users and developers have expressed interest in having an SDK for these newer models, but so far, there has been no official response from Fitbit regarding future support[1][11].
Citations:[1] https://stackoverflow.com/questions/73916842/how-can-i-enable-versa-4-usb-debugging
[2] https://store.google.com/product/fitbit_versa_4_specs?hl=en-US
[3] https://community.fitbit.com/t5/SDK-Development/Building-and-publishing-clocks-faces-apps-for-Versa-4-and-Sense-2/td-p/5446484
[4] https://forum.urbandroid.org/t/fitbit-versa-4-integration-for-sleep-as-android/10124
[5] https://support.google.com/fitbit/answer/14237105?hl=en
[6] https://umes.bncollege.com/FITBIT/Fitbit-Versa-4-Fitness-Smartwatch--Pink-Sand/p/698043546
[7] https://www.youtube.com/watch?v=4Aa_70SusG0
[8] https://staticcs.fitbit.com/content/assets/help/manuals/manual_versa_en_US.pdf
[9] https://community.fitbit.com/t5/SDK-Development/Fitbit-Versa-4-SDK-support/td-p/5570528
[10] https://www.reddit.com/r/fitbit/comments/xnoog9/psa_the_new_sense_2_versa_4_do_not_support/
[11] https://community.fitbit.com/t5/Product-Feedback/idb-p/features/label-name/sdk