In March 2015, Apple announced a new iPhone application development framework for medical research called Research Kit. Research Kit makes it easy for investigators and software developers to build applications for collecting medical research data. No doubt investigators are excited by the potential for Research Kit. Hundreds of millions of people have iPhones, and may now contribute their iPhone data to medical research on a scale that has not been available before. The Research Kit framework provides 3 customizable modules that address common elements of medical research studies: informed consent forms, surveys, and real-time active tasks (e.g., gait and tapping motor activities, 6-minute walk tests of fitness, spatial memory tests of cognition, and phonation voice tests). Modules take advantage of iPhone sensors and capabilities for tracking movement, taking measurements, and recording data. New modules may also be developed and integrated with iPhone’s health and fitness data collection capabilities (e.g., daily step counts, calorie use, sleep-wake cycles, nutrition, and heart rates).