Sparkline collects and displays continuous real-time feedback. It has an interface for users to continuously adjust a relative rating scale and a constantly updating sparkline of the average rating.
One application of this the Sparkline tool is large lecture courses or distance education settings, where obtaining timely student feedback is highly desirable, but generally a difficult or time-consuming undertaking. An instructor can ask students to decrease their rating as the lecture progress if they think the instructor is going too fast or they aren't understanding the material, or to increase their rating if they think the instructor is going to slow or the material is unnecessarily remedial. As the instructor presents, they (or an assistant) can monitor the rating sparkline and adjust their presentation accordingly, perhaps skipping remedial slides, or stopping to figure out which part students didn't get and trying a different approach to explaining it.
The sparkline Sparkline graphical display is generated using the "Sparklines for Java" library.