If weight management is one of your goals, you can log your weight right in the app with just a few taps! You can change units at any time by going to Profile -> Settings -> In-app units.
You can then see your weight and your progress from your timeline or by visiting your profile.
If you need to change the units from lbs to kg or vice versa, you can do this by going to the top-left menu and tapping App Settings. Here you can select your preferences for units.