Asking Apple's iPhone 4S personal voice assistant Siri, "What is the best smartphone ever?" pointed users to the Nokia Lumia 900, according to user reports.

Apple Siri launch logo

However, Apple seems to have replaced the answer with a generic response that instead replies: "Wait... there are other phones?"

The swap led Nokia to accuse Apple of censoring the results.

"Apple positions Siri as the intelligent system that's there to help, but clearly if they don't like the answer, they override the software," Nokia spokeswoman Tracey Postill told the Sydney Morning Herald.

The original response naming Nokia's Lumia 900 as the best smartphone was based on results from the Wolfram Alpha search engine.

That computational search used reviews posted on the US Best Buy website to make its decision.

Now when the same question is asked the Wolfram Alpha search is bypassed and the default response is triggered.

In December 2011 Apple denied that Siri deliberately avoided listing local abortion clinics, after it was found the application offered information on "anti-choice crisis pregnancy centres" instead.

Apple also won its case with the Advertising Standards Agency in March 2012 over allegedly misleading Siri advertisements in the UK, when a user pointed out that the location functions worked only in the US and not in Britain.