The app, which is available for free download, opens with a "Try our new voice search" message that sits next to an icon of a microphone. Click on the icon and speak your question into your device.
If the answer to your question is short, Google will tell you the answer aloud. If the answer is more complicated, the user will get a list of possible answers and links on the screen.
"Getting an answer is as simple as tapping on the microphone icon and asking a question like, 'Is United Airlines flight 318 on time?' " wrote Kenneth Bongort, a Google search engineer, in a blog post. "You can get answers to an increasingly wide variety of questions thanks to Knowledge Graph, which gives our search technology an understanding of people, places and things in the real world."
Knowledge Graph, which was introduced this past May, first appeared as an extra column on the Google search results pages. It was designed to help the search engine dig deeper into search requests by asking users to be more specific about what they're searching for.
By combining the technology behind Knowledge Graph and voice recognition, Bongort said Google's search app now can answer questions like, "What does Yankee Stadium look like?" and offer up hundreds of pictures.
Ask it for a trailer of the new James Bond movie and the video should start playing inside Google Search.
"I think in this era of hands free being the norm, voice search can be very helpful to users," said Zeus Kerravala, an analyst with ZK Research. "It allows fast lookup of information in natural language form, particularly for highly mobile individuals for whom the process of inputting information onto a small screen is cumbersome to impossible."
However, in the wake of the mainstream hubbub surrounding Apple's 2011 release of its Siri voice search, Google has a lot of ground to make up, according to Kerravala.
"I do think Siri has stolen most of the mindshare," he added. "Apple has been very aggressive promoting Siri, while Google has done very little with voice-enabled search."
This past June, Google unveiled, at its annual I/O developer conference, the latest upgrade to its Android operating system - Android 4.1 or Jelly Bean. One of the more interesting aspects of Jelly Bean was the Google Now smart assistant.
The Google Now voice service was an obvious competitor to Apple's Siri, which was introduced with the iPhone 4S last fall.