Shop-Alarm is a Firefox browser add-on designed to integrate charitable donations into online shopping experiences. This subscription-based tool connects users with over 30,000 partner shops, enabling them to contribute a portion of their purchases to various charitable organizations without incurring additional costs. The add-on features an intuitive popup that appears when users visit a partner shop, providing a 'Help' button to facilitate donations easily. Users can also customize the frequency and visibility of popups according to their preferences, making the experience tailored to individual shopping habits.

Privacy is a core focus of Shop-Alarm, as it does not track users' browsing data. It loads the list of partner shops at startup, ensuring there is no continuous connection to external databases while users shop. With the responsive design introduced in version 3.3, Shop-Alarm is also optimized for smartphone use, enhancing its accessibility and usability for charitable giving while shopping online.