We sync a few data points when you log your weight with an App Gallery scale partner.
WEIGHT
Your weight entry for the current date will be updated in your MyFitnessPal account whenever new weight data is synced from your connected scale to the scale's website. This weight will be updated to the nearest single decimal value.
BODY FAT %
When you first link your MyFitnessPal account with a scale partner that measures your body fat percentage, a new body fat percentage measurement will be added to your Check-In/Progress area. When the partner's scale records your body fat percentage, this data point will sync to the scale's website, and then to MyFitnessPal. Please note: not all partners will sync body fat %