Apple Inc. will introduce a new version of the iPhone on Tuesday, the first upgrade of its best-selling product since Steve Jobs resigned as CEO. “Let’s talk iPhone,” Apple said in an invitation to the gathering at its headquarters in Cupertino, Calif.

The new iPhone will include a better camera and faster processor, people familiar with the product said earlier this year. Introduced in 2007, the iPhone accounts for about half of Apple’s revenue. Demand for the touch-screen gadget has helped catapult Apple ahead of Exxon Mobil Corp. as the world’s most valuable company.