The technology that allows for instant feedback during user testing is commonly known as User Experience (UX) Testing tools or frameworks. These tools facilitate real-time observation of user interactions with a product, providing valuable insights into usability issues and user satisfaction. Techniques like A/B testing, remote usability testing, and heatmaps enable developers and designers to quickly gather data, analyze user behavior, and iterate on designs based on immediate user feedback. This iterative process enhances product design and functionality, ultimately leading to a better user experience.