How Apple used Google’s help to train its AI models

Last week, CEO Tim Cook’s Apple (AAPL.O) announced a splashy deal with OpenAI to include its powerful artificial intelligence model as a part of its voice assistant, Siri.

But in the fine print of a technical document Apple published after the event, the company makes clear that Alphabet’s Google (GOOGL.O) has emerged as another winner in the Cupertino, California, company’s quest to catch up in AI.

To build Apple’s foundation AI models, the company’s engineers used its own framework software with a range of hardware...