(Reuters) -Apple on Tuesday took the wraps off newer variants of some of its best-selling devices, hoping that they make it to the top of wish list of customers during the all-important holiday shopping season.

The announcement of the iPhone 15 line and upgraded smart watches at the company's annual flagship event comes against the backdrop of flagging discretionary spending and heightened scrutiny in China.

Apple also switched to the USB-C charging standard from Lightning port, in accordance with a European law, on its latest iPhones, and announced environment friendly changes to some of the devices.

Here are the details of the key announcements:

The iPhone

Apple launched iPhone 15 and iPhone 15 Plus, sporting 6.1-inch and 6.7-inch displays, respectively, similar to their predecessors.

The higher-end iPhone 15 Pro and iPhone 15 Pro Max models, priced at $999 and $1,199, respectively, now use titanium instead of stainless steel for the side bars and have slimmer borders around the screen.

All the new models feature a 48-megapixel main camera, with flagship Pro Max having 5X optical zoom and 3X telephoto capability.

The iPhone 15 and iPhone 15 Plus get A16 bionic chip, while the iPhone 15 Pro and iPhone 15 Pro Max will be powered by the A17 pro chip.

Apple also said the batteries of iPhone 15 and iPhone 15 Plus, which start at $799 and $899, respectively, are made of 100% recycled cobalt.

Watches

Apple announced Watch Series 9 and the second generation of Watch Ultra, sporting the same dimensions as their predecessors.

The latest watches get the next generation S9 chip, capable of better animations and effects. It is the first processor upgrade since Apple released the Series 6 line in 2020.

New features on board include "double tap", a new gesture control to the watch without touching its face, and improved dictation and brightness.

The Series 9 starts at $399, while the Ultra 2, at $799, is priced at the same level as the earlier base model, and will be available from Sept. 22.

The Series 9 is the company's first carbon neutral product, and starting this year all watch manufacturing will be powered by 100% clean energy, the company said. Apple will also drop leather from all its products, including the watch bands.

(Reporting by Yuvraj Malik in Bengaluru; Editing by Sriraj Kalluvila)