In-n-Out is a California institution. To help push more of its delicious burgers and shakes, I created a limited-time promotion that leans into another California institution: earthquakes.

Californians experience minor earthquakes on a weekly basis. Usually they cause no damage at all, but instead, create a lot of excitement on social media. So when a small earthquake occurs, In-n-Out’s app alerts you to the deals available, calculated based on strength of earthquake and how far you are from it.

Social media posts drive people to download the app.