Scurry! is a social step counting app (and distance and flights climbed too...). Scurry! is currently able to take data from Apple Health (which users your iPhone for data, but also incorporates Apple Watch if you have both) or choose to import Fitbit data.
Users can then compare step data with their friends with a daily chart as well as a weekly tally.
With Scurry! you can not only hit your own goals, but encourage your Facebook friends / iPhone contacts to as well!