Apple is hosting an event on Tuesday and is expected to release one of the most highly anticipated iPhones yet, likely featuringa more colorful screen and a redesigned body with sensors that detect a user’s face.

  • Apple shares are up less than half a percent as the company discusses updates to the Apple Watch.

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Apple Watch is the #1 watch, ahead of traditional brands, CEO Tim Cook says, with over 50 percent growth compared to the previous year. Jeff Williams, chief operating officer, said that Apple is adding new measurements to the heart rate readings of the Apple Watch, like recovery heart rate.

Angela Ahrendts, Apple’s senior vice president of retail, said foot traffic to Apple Stores tops 500 million each year, amid the company’s store overhaul. Chicago’s Apple Store will open next month on Michigan Ave, she said.

The launch also marks the public debut of the Steve Jobs Theater on Apple’s new 175-acre campus. The new theater and introduction of the iPhone X correspond with the 10th anniversary of the original iPhone.

“It is the honor of a lifetime to be the first to welcome you to the Steve Jobs Theater,” Cook said, taking the stage after audio from Jobs played overhead. “Steve was a genius.”

CNBC’s Josh Lipton and Megan Hawkins visited the campus early, viewing the new glass “spaceship” and rubbing shoulders with Apple co-founder Steve Wozniak.

Apple’s new hardware will build on software announced earlier this year at the Apple Worldwide Developers Conference, where the company promised to create an augmented reality platform that would let app developers create interactive services for iPhone users.

Creating an ecosystem that keeps users engaged could be key in satisfying Wall Street’s lofty expectations and maintaining Apple’s status as the most highly valued public company in the world. If Apple successfully impresses consumers with its new devices, it could be on track to become a trillion-dollar company.

Analysts have largely brushed off Apple’s quarterly financials this year, looking toward the holiday season and the new crop of devices. Apple is expected to sell a record 85 million iPhones in the quarter ending in December, according to FactSet. That could include over 300 million upgrades, according to former Apple analyst turned venture capitalist Gene Munster.

Apple has contributed to the latest buzz by lifting its revenue guidance. The company said in August that it expects fiscal fourth-quarter revenue of $49 billion to $52 billion, topping estimates at the time.

Apple shares have jumped 53 percent in the past year, more than triple the gains for the S&P 500.

— CNBC’s Arjun Kharpal, Todd Haselton, Megan Hawkins and Josh Lipton contributed to this report.