(Bloomberg) -- The Apple Inc. executive in charge of product design for the iPhone and smartwatch is stepping down, bringing a shake-up to the company’s most critical product lines.Most Read from BloombergApps That Use AI to Undress Women in Photos Soaring in UseThe Record Rush to Buy a Rolex or a Patek Philippe Is OverAmericans Rush to Portugal Ahead of Changes to Expat Tax BreaksCarlyle’s Rubenstein Is in Talks to Acquire Baltimore OriolesHunter Biden Indicted in Tax Case as White House Woes M