Siri received a C+ while Google Now also got a C+. Both improved their grades with the former jumping from a grade of C and the latter leaping from D-. The personal assistant programs have gone through another test and results revealed that Siri improved, but Google Now is catching up.

Gene Munster of research firm Piper Jaffray subjected the voiced-driven mobile tools to 800 questions and found out that the two are almost at par with each other. Munster also compared the grades of Siri and Google Now to their marks last year.

"Google Now and Siri are comparable in terms of understanding the spoken queries and returning the correct result. Google Now and Siri both correctly understood 94 percent of total queries regardless of environment (noisy or quiet). In terms of accuracy of answer, we determined that Google Now accurately answered understood queries 81 percent of the time compared to 83 percent for Siri, but when factoring in all queries (our "Net Ability), both Google Now and Siri answered 79 percent of queries," said Munster in a new report.

Last year, Siri just got 77 percent of the questions correct while Google Now got 61 percent correct.

According to the analyst, the grade of Siri being higher in iOS 7 compared to the iOS 6 is due mainly to the systems ability to hear better in noisy environments, with 94 percent heard correctly in iOS 7 and just 84 percent in iOS 6. Google Now hears the user in a noisy environment 92 percent of the time in this year's test, compared to just 78 percent last year.

Siri is also starting to rely more on WIkipedia, Wolfram Alpha, and Bing results to provide better answers instead of just Google. In the recent test of Piper Jaffray, Siri only relied on the leading search engine for 4 percent of its total answers while depending more on WolframAlpha (12 percent), Bing (15 percent), Wikipedia (9 percent), and Yelp (33 percent).

Looking at the different categories, Siri edged Google Now significantly in following OS commands with grades of 85 percent and 61 percent, respectively. Google's voice assistant proved its wits in the navigation, information, and local categories garnering higher grades than Siri.

Apple shares closed 0.74 percent down at $561.36 on the NASDAQ on Wednesday, while Google shares were down 0.68 percent at $1077.29 on the same exchange.