Google explains how it created ultrasonic features for Nest smart displays
(Android Central)

They`ll also soon work in even more ways. What you need to know Google rolled out ultrasonic sensing features last month to Nest displays, something that was inspired by a Googler`s older father walking closer to the display to read information. The feature uses inaudible sound waves to detect when a person is near or far away from the display and changes the size of the text on the screen. It currently works with timers, commute times, and weather. Support for reminders and appointments are coming soon. Back in November, we reported on a new feature in Nest smart displays such as the Nest Hub and Nest Hub Max which reacts based on your proximity to the device. For example, when setting a timer, the numbers on the display become larger when you`re further away from the screen. Now, Google is detailing on its blog how this feature came to be and new ways it will be used in the near future. It turns out the feature originated after a Googler noticed how their father would walk c...