More: It's for iPhones and Androids. The article doesn't say anything about a desktop version.
Based on the app's window size, it is obviously written for the iPhone, but I have been testing it on my Mac Studio running Sonoma, my iPad Pro running iPadOS 17 and iPhone Pro running iOS 17. Whether or not it will run on Intel Macs is beyond my ability to test, so I will leave that up to you. The app generates and sends a signed email to the site manager requesting them to honor their policy and remove your information from any information given to a third party. The request is eloquently phrased as s polite demand, The app's efficacy is dependent on the site following its own published policy and subject to legalistic interpretation but its association with Consumer Reports adds significant weight.