Apple on Wednesday started integrating OpenAI's ChatGPT into its devices, delivering on a long-awaited feature that investors hope will help drive sales of its latest iPhones.

The rollout is part of a wider deployment of artificial intelligence-powered tools in the latest updates to the operating systems for iPhones, iPads and Mac computers.

The ChatGPT integration, announced in June as part of the Apple Intelligence unveil, will allow the company's Siri voice assistant tap the chatbot's expertise including on user queries about photos and documents such as presentations.

Users can also ask ChatGPT to create written content in any app that supports the new Writing Tools feature. They can use the chatbot's image generation capabilities to add images.

The move comes during the peak holiday shopping season, the company's most lucrative sales period of the year. The slow rollout of Apple Intelligence features so far has raised some investor worries about the strength of the iPhone 16 sales cycle.

The AI features will be available on the latest iPhone series, as well as the Pro and Pro Max versions of the previous iPhone 15 line-up. Users of iPad with A17 Pro or M1 chips and later, and Mac with M1 chips and later can also access the tools.