The author of a macOS app called Restaurants, which used the Yelp API to help users find restaurants, received an email from Yelp stating that they would need to obtain a paid license to continue using the API. The author was given only 4 days' notice, which they felt was insufficient and unprofessional. The app had been using the Yelp API for 10 years and had been driving traffic to Yelp's website. The author ultimately removed the app from sale due to the high cost of the paid license.