Why Smartphone Virtual Assistants Will Be Taking Over for Your Apps Soon by Barb Darrow @FortuneMagazine December 21, 2016, 9:42 AM EST E-mail Tweet Facebook Linkedin Share icons Right now, smartphone owners use Siri, Cortana, and Google Now at least sporadically to verbally request directions, send texts, get information, or control their devices. But that practice will become much more common over the next four years, according to a new survey by IT research firm Gartner. These assistants will take over the jobs now handled by myriad mobile apps, the researchers say. That may come as a relief to those of us who suffer from app fatigue. Gartner it estimates that within four years, 20% of phone interactions will rely on what the company calls Virtual Personal Assistants (or VPAs). From the report summary: Today, VPAs are fulfilling simple tasks such as setting the alarm or retrieving information from the web, but in the near future these systems will be able to deliver more complex tasks such as completing a transaction based on past, present and predicted context. As of this year, 42% of U.S. smartphone owners surveyed said they had used their phone’s VPA over the past three months. That compares to 32% of users surveyed in the U.K. More than a third of consumers in both countries used their smart assistant at least once a day, according to the survey. Apple‘s Siri and Google googl Now are the most popular VPAs, cited in the survey. More than half (54%) of respondents in the U.S. and U.K. said they had used Siri in the last three months. Google Now was used by 41% of U.K.-based respondents and 48% of U.S. respondents in the same period. Gartner surveyed just over 3,000 smartphone users across the U.K., U.S., and China on these points. Get Data Sheet, Fortune’s daily tech newsletter. Microsoft Cortana is something of a wild card given that company’s weak track record in smartphones. Then again, Cortana can run on iPhones and Android devices. And, by integrating Cortana with Skype, Microsoft will—in theory—enable millions of Skype users to parlay Cortana to book fights, hotels, and more. Update: Another wild card not mentioned in the report summary is Amazon amzn Alexa, which is a home-focused service working with the Amazon Echo hub device and third party devices. There is an app make your smart phone a “companion device” for Echo and other Echo-connected devices, an Amazon spokeswoman confirmed, adding “that you don’t speak to Alexa on your phone.” While Amazon Fire phone was a dud, it’s possible Amazon could make Alexa more of a general purpose assistant for smartphones, but time will tell. Gartner analysts said the market for smart assistants isn’t all about smart phone assistants: Facebook fb Messenger can be used to for shopping and other tasks. For more on smart virtual assistants, watch A virtual assistant is only as smart as the artificial intelligence powering it and its ability to learn from requests over time. As a result, Gartner research director Annette Zimmerman said in a statement that AI, machine learning, and VPAs together will be a major strategic battleground going forward. As a result, many mobile apps will take a hit and “become subservants” of VPAs in the foreseeable future. By 2020, Gartner also expects that “zero-touch” user interfaces will be available on 2 billion devices including smartphones and Internet of things devices. Editor’s Note: This story was updated to include Amazon’s comment.