Shake Shack has an offer for Buy One Burger, Get One Free (up to $6 maximum) via their app. If you are hungry for lunch or dinner, check this one out! Yes!
Use promotion code:
Shake Shack BOGO!
Offer is available for one-time use only until 10/26/2018 at all participating Shake Shack locations on the Shack App or in-person at most Shake Shack locations, excluding airports, ballparks and stadiums. Max savings of $6. Minimum Shack App + kiosk order of $10 for offer to apply. Discount will be applied at checkout. More information can be found here.
HT: little pigs via Slickdeals