Microsoft has tried very hard to promote Cortana more widely, but statistics published as part of a survey conducted by measurement firm Verto Analytics show that Apple's Siri continues to be number one in the United States with at least 41.4 million monthly unique users.
Cortana is far behind with just 0.7 million monthly users, although Microsoft's assistant has improved compared to the same period last year. Cortana, however, tripled its share from 19% to just under 60%.
There's a reason for the big difference between Siri and Cortana: the survey only analyzed mobile usage, not desktops, and given the market share difference between iPhones and Windows phones, it's not surprising that Apple got the better score.
According to the same statistics, the average time spent using Siri each month has decreased from 39 minutes to 14 minutes, while Cortana has actually improved to a record 2 hours and 31 minutes. This means that users find Cortana much more engaging, with Google's Allo coming in next at 2 hours and 30 minutes.
Google Assistant has 1 million monthly unique users according to statistics, while Alexa has around 2.6 million users.
But even if Siri is first, statistics show that usage has declined from the same month last year to less than 15 percent or 7.3 million monthly users.
Both Microsoft and Apple are betting big on their digital assistants, and both companies are already working on a series of updates for future versions of their operating systems.
The survey was conducted among 20,000 American consumers between May 2016 and May 2017 and also included consumer research data.
