Google’s Advanced Technology and Projects group first unveiled Soli in 2015, but it did not launch on a consumer device until 2019. The sensor lets you perform air gestures over the Pixel 4 to play/pause and skip/rewind tracks, as well as snooze alarms and silence phone calls. It’s also used to speed up face unlock by detecting when users reach for their phone and turning on the components needed for recognition. Third-party Android developers can incorporate the tech, which emits radar waves, into games and other interactive experiences. Meanwhile, the new Nest Thermostat also leverages it for improved motion sensing...