To sync your Health Kit with World Walking you must first of all enable HealthKit by logging into the World Walking app, clicking on ‘Apps’ and then activating Health Kit. Once you have done that, you can verify World Walking is connected to HealthKit by opening the ‘Settings’ app on your iPhone, then going to ‘Privacy’ and then ‘Health’ and making sure the check beside Steps is enabled.
Once enabled, the next time you open the World Walking app it will automatically bank any steps recorded through Health Kit since you last used the app.
If it is enabled and you are still having problems, please try restarting your phone or re-installing the World Walking app.