Apple hits $4tn market value as new iPhone models revitalize sales

Tech company's stock enters positive territory for first time this year after gaining about 13% since new iPhone launches

Apple topped $4tn (3tn) in market value for the first time on Tuesday, joining Microsoft and Nvidia as the third company in history to hit the milestone, thanks to strong demand for its latest iPhones.

Apple's share price has increased by more than 50% since a low point in April, thanks to the debut of its latest products.