Lifesum supports Sign In With Apple for all devices running iOS 13 and later.
You find the option above our existing options of signing up with Email or Facebook.
Existing users can add sign in with apple as an option for their account if the email on their account is the same as their Apple ID:
  1. If logged into another account, first log out.
  2. Press "Log In".
  3. Press "Sign in with Apple".
  4. Choose to share email, so that the email matches the existing Lifesum account.