Biosensors capable of monitoring physiological conditions from compounds collected noninvasively from external bodily fluids have been actively developed to realize personalized predictive medicine. Sweat is one of the most attractive bodily fluids for analysis of physiological conditions because of its easy access to the human skin surface and as a potential source of blood-derived biomarkers. However, the repetitive sampling of at-rest sweat required for biosensing is one of the greatest challenges in achieving the continuous monitoring of human health. In this paper, we summarize the recent development of a new type of biosensor that effectively and repeatedly collects and detects at-rest sweat components in a safe and easy manner by employing a hydrogel touchpad-based wet interface between the device and skin. In the future, the hydrogel touchpad-based sweat biosensor will allow individuals to track changes in sweat composition to realize daily self-health management.