The Google Assistant was limited to the technology company's own products when it was released last fall, but it has steadily been expanding to a broader range of devices.
Smartphones running Android accounted for 85 percent of the global market last year, according to tech research firm IDC, compared to 15 percent for Apple Inc's iOS.
The Google Assistant will roll out this week to English speakers in the United States with phones running Android 7.0 Nougat and Android 6.0 Marshmallow, the company said.
English speakers in Australia, Canada and the United Kingdom will gain access to the assistant next, followed by German speakers in Germany, and the company is working on support for additional languages.
Voice-powered digital assistants have been largely a novelty for consumers since Apple's Siri introduced the technology to the masses in 2011. But many in the industry believe the technology will soon become one of the main ways users interact with devices, and Apple, Google and Amazon.com Inc are racing to present their assistants to as many people as possible.