Apple launched a new series of iPhones that included a new titanium shell, a faster chip and improved video game playing abilities.

The biggest surprise with the iPhone 15 that will come out Sept. 22: It did not raise prices, reflecting the global smartphone slump.

The event at Apple's Cupertino, California, headquarters comes amid lingering economic uncertainty, especially in China, Apple's third-largest market where it faces challenges from expanded restrictions on using its iPhones in government offices and the first new flagship phone in several years from Huawei Technologies.

Huawei raised its second-half shipment target for the new Mate 60 series smartphone, which has satellite capability, by 20%, the country's official Securities Times reported on Tuesday shortly before the Apple event.

Apple did not deliver any blockbuster surprises, and shares closed down 1.7% after event.

Apple embedding machine learning

While Apple avoids the terms artificial intelligence, or AI, the technology was the driver of several new features.

An Apple executive said the company used machine learning to detect a person in the frame, allowing users to turn a picture into a portrait immediately or later in the Photos app.

Apple also showed off new watches, including a Series 9 Watch with a feature called "double tap" where users tap thumb and finger together twice, without touching the watch, in order to perform tasks like answering a phone call.

It uses machine learning to detect tiny changes in blood flow when the user taps their fingers together, freeing up the other hand for other tasks like walking a dog or holding a cup of coffee, said Apple Chief Operating Officer Jeff Williams.

iPhone 15 launch

Both the Pro and other iPhone 15 models will have a brighter display and a 48-megapixel camera as well as 100% recycled cobalt in their batteries.

Apple said the iPhone 15's satellite connectivity can now be used to summon roadside assistance. It is rolling out the feature out with the American Automobile Association (AAA) in the United States.

Apple said that USB-C charging cables are coming to both its iPhone 15 and the charging case of its AirPods Pro devices. The move reflects requirements from European regulators to use USB-C and allows the use of the same charging cables already used for iPads and Macs.

"I was expecting Apple to try and spin the all USB-C decision in certain way but they didn't they were very matter of fact in the way they talked about it," said Carolina Milanesi, an analyst with Creative Strategies. She said the shift "brought some differentiation to the iPhone Pro, because there's faster throughput for data transfer. That is going to be valuable for people" who use the device for professional photography, Milanesi said.

Apple also said the iPhone 15 Pro can capture what it calls "spatial videos" by using two of the device's cameras to capture a three-dimensional video. Those videos will be viewable on Apple's Vision Pro headset that is due out early next year, marketing chief Greg Joswiak said.

The Pro's use of titanium makes it lighter and stronger than previous models of other metals.

Bob O'Donnell, head of TECHnalysis Research said the steady prices were a surprise.

"I think both Apple and the carriers recognize that with consumers feeling pressure on their budget and the lack of dramatic changes it’s getting harder to convince people to upgrade. Keeping prices stable should help with that," he said.

The iPhone 15 costs $799, the iPhone 15 Plus starts at $899 and the Pro series starts at $999. The Pro Max starts at $1,199, the same prices as last year for the same levels of storage. Last year, Apple offered a $1,099 iPhone Pro Max model with less memory.

Apple still relies on iPhone for more than half of its sales, but the global smartphone market has slumped from shipping 294.5 million total phones to 268 million in the second quarter. Apple's shipments declined the least of any major smartphone maker, dropping from 46.5 million phones to 45.3 million, according to data from Counterpoint Research.

New watch out

The outdoor sports-focused Apple Watch Ultra 2 has new features for cycling and diving and what Apple said is the brightest screen it has ever made. The Series 9 will start at $399 and the Ultra 2 watch will start at $799 and be available Sept. 22.

Apple will no longer use leather in any of its products, said Lisa Jackson, the company's environmental chief. The company is replacing some of those products with a textile called "FineWoven" that it says feel like suede.

Apple made its effort to become carbon neutral by 2030 a focus of the event, including launches of lower-carbon watches.