Digital Wellbeing is a feature built into the Android system to monitor device usage patterns and the collected data can help users to be less obsessed with screens and use devices wisely so as not to harm physical and mental health. Most recently, Digital Wellbeing can warn when one application is used for too long at a time.
This feature is Screen time reminders which remind users how much time has been spent in one application. This reminder will be displayed in the form of a notification similar to the Dynamic Island display on the iPhone. The feature doesn't say when the reminder will be given but based on the screenshot, if one app has been open for more than 15 minutes without switching to another – a reminder will start appearing.
Among the benefits of this feature is that it will give awareness to users not to be complacent and be aware of the time that has been spent on the device screen. This can indirectly ensure that users become healthier and not obsessed with smart device screens.