Apple's longtime head of marketing is stepping aside, marking the 3rd high-profile leadership shakeup at the company in the last 18 months (AAPL)

· Apple's longtime head of marketing, Phil Schiller, is stepping aside, Apple announced Tuesday. 
· Schiller will remain at the company as an Apple Fellow, while another longtime employee, Greg Joswiak, takes his place. 
· The change marks the third high-profile leadership shakeup since early 2019 and comes as Apple is...