Phone Factory calibrates proximity sensors, speakers, and haptics so calls sound clear, taps feel precise

https://www.livebinders.com/b/3704652?tabid=15dd4bf4-a1d8-5747-8b6c-07fdf1003e7e

Phone Factory calibrates proximity sensors, speakers, and haptics so calls sound clear, taps feel precise, and your device behaves just like new.