Yes, the app can sync with smart weighing scales.
Most modern scales send weight data to their companion apps via Bluetooth or WiFi. If those apps support syncing with Apple Health, Samsung Health, or Health Connect, the app can automatically read weight data from them.
For example, if your scale syncs with Apple Health, Health Connect or Samsung Health, you’ll see your weight updates in the app without entering them manually.
Alternatively, it's possible to establing direct syncing with Fitbit, Garmin, or Withings.