A Withings scale gives Beacon a weight trend it doesn't have to ask you for. The connection is deliberately narrow.
What Beacon reads
Weight and body-fat percentage. Nothing else.
Beacon asks Withings for one permission — body measurements — and reads only real measurements, ignoring any goal weight you've set in the Withings app. Where you step on the scale more than once in a day, the last reading of that day is the one Beacon keeps, in your account's own timezone.
If you own a Withings sleep mat, blood-pressure monitor or watch, Beacon does not read them. There is no permission requested and no code to do it.
What Beacon writes back
Nothing. Read-only.
History and freshness
Connecting imports 90 days of weigh-ins. After that, Withings notifies Beacon when a new reading arrives, and a poll every 15 minutes covers anything the notification misses — including a scale that was offline and uploaded several days at once.
Good to know
- Apple Health usually wins on the same reading. If a weigh-in reaches Beacon through both Withings and Apple Health, Beacon prefers the richer source. Withings is ranked last on purpose, because it supplies only these two numbers.
- Disconnecting deletes the Withings data Beacon holds. Reconnecting re-imports what Withings still has, and for a short gap Beacon fetches only the days it missed rather than the full 90.
- A weigh-in completes a weigh-in habit by being logged, whatever the number says. There's no target to hit for the habit to count.