Google's artificial intelligence-based voice Assistant is on more than 100 million devices now, and the company is leveraging a longtime competitor to expand the technology to even more people. 

At its developer conference on Wednesday US time, Alphabet's Google said it was launching the Assistant as an application for Apple's iPhone.

The app will support many of the same functions as the service does on Google devices.

Users will be able to integrate with Gmail and control home appliances, Google said.

The application will become available first for users in the US and support English. Other countries and languages will come later.

Google also discussed a software development kit for the Assistant, which will allow third-party hardware makers to integrate the tool into their own products.

Google said the expansion of the Assistant to the iPhone and various other third-party products should increase its reach beyond the current 100 million devices.

The Assistant can now converse in French, German, Brazilian Portuguese and Japanese.

By the end of the year, the system will understand Italian, Spanish and Korean, Google said.