Analyst's test shows Google Now gaining on Apple's Siri

A customer tries the Siri voice assistant function on an Apple Inc.
Ian Waldie | Bloomberg | Getty Images

Google's gaining on Apple again.

The search giant's voice-activated search service, Google Now, is just as good as Apple's Siri, according to test results released Tuesday from Piper Jaffray analyst Gene Munster.

To determine performance grades, he asked the two smartphone assistants 800 questions, tracking their ability to understand and respond helpfully.

Munster compared the results to those from last year, when he conducted a similar test.

While Google Now may improving faster than Siri, neither service came close to a top grade.

Both scored a C+ (the former up from a D- last year and the latter from a C).

Read more on the USA Today website.

By CNBC's Cadie Thompson. Follow her on Twitter @CadieThompson.