But if the user does not acknowledge the alert, the device will automatically reduce the volume to a predetermined level (based on the mode selected, i.e. 80 or 75 dBA). By conveying exposure information in a way that can be easily understood by end-users, this recommendation aims to make it easier for listeners to manage their exposures and avoid any negative effects. The health app on iPhones, Apple Watches, and iPads incorporated this approach starting in 2019.[40] These feature the opt-in Apple Hearing Study, part of the Research app that is being conducted in collaboration with the University of Michigan School of Public Health.