The battle of the virtual public assistants is getting more complicated.
Later this week, Google is expected to announce plans to bring its popular Google Assistant voice-activated app to the Apple iPhone, according to a Bloomberg report.
That would put Google Assistant, already available on Android phones, in more direct competition with Apple (AAPL) Siri, the technology that blazed the trail for voice-activated phone interaction. Cortana, the Microsoft (MSFT) voice assistant, is already available on Apple iTunes for use on iPhones and iPads.
Siri’s advantage will remain that it is preloaded on the popular iPhones, while users will have to download the other non-Apple options.
Related: Amazon Really Wants Alexa to Run Your Home
The news should come at the Google I/O tech conference in the Bay Area, which kicks off Wednesday. Fortune contacted Google (GOOG) for comment and will update this story as needed.
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All the major software giants are pushing their own virtual personal assistants to consumers. Aside from being handy for people who use them to get directions, find songs, look up phone numbers, and dictate texts, these virtual assistants also funnel lots of valuable consumer information back to their home base at Google, Apple, or Microsoft.
That data is then used by the companies to fine-tune their artificial intelligence (AI) algorithms, to make their software smarter and able to return better results in the future. That data hoovering process also alarms some consumers who wonder if trading convenience for their information is really a great idea.
Related: Smartphone Virtual Assistants Will Take Over for Your Apps Soon
Amazon (AMZN) initially took the home appliance approach to virtual assistants with Echo, a voice-activated home speaker powered by Amazon’s Alexa voice recognition software. But, as of this year, Alexa is showing up on some Huawei and HTC phones as well.