Checkin on Foursquare with hashtag #unlock and automatically unlock your SmartThings lock.
If
New check-in tagged
This trigger fires every time you check in on Foursquare or Swarm with a single hashtag in the shout (e.g. #IFTTT).
Fewer details
ID ukixTm3R
Discover more time saving integrations for SmartThings (Legacy) and Foursquare