Smartphone is emerging as a portable analytical biosensing platform in many point-of-care (POC) applications such as disease diagnostics, environmental monitoring, and food toxin screening. With the recent advancement of imaging technologies on the smartphone, the manual control of acquisition settings (e.g., exposure time, frame rate, focusing distance, etc.) has already been expanded from the photo to the video capturing mode. In modern smartphone models, high frame rate (above 100 fps) can be achieved to bring in a new temporal dimension to the smartphone-supported POC tests by recording high-definition videos. This opens up a new analytical method defined as smartphone videoscopy. In this review, the recent development of smartphone videoscopy is summarized based on different POC applications. Representative examples of smartphone videoscopy systems and how these time-dependent measurements could open up new opportunities for POC diagnostics are discussed in detail. The advances demonstrated so far illustrate the promising future of smartphone videoscopy in biosensing, POC diagnostics, and time-resolved analysis in general.