User-smartphone interaction in more intuitive ways has become a trend today due to the advancement of various technologies. Thus, Gartner predicts that by 2019, 20% of all user interactions with the smartphone will take place via virtual personal assistants (VPAs).

Apple's Siri and Google Now are the most widely used VPAs on smartphones. Fifty-four percent of UK and U.S. respondents in Gartner's annual mobile apps survey used Siri in the last three months. Google Now is used by 41% of UK respondents and 48% of U.S. respondents. "VPAs' usage is bound to accelerate as they add many new features, including integration for business services, further language support and appear across more devices," said Jessica Ekholm, research director at Gartner.

Gartner expects that by 2019, VPAs will have changed the way users interact with devices and become universally accepted as part of everyday life. 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.

This trend is also intensified by the acceleration of conversational commerce, but voice is not the only UI for VPA use. In fact, Facebook Messenger is allowing users to interact with businesses to make purchases, chat with customer services and order Uber cars within the app. Moreover, Tencent's WeChat generates over $1.1 billion in revenue by offering its 440 million users an all-in-one approach, letting them pay their bills, hail cabs and order products with a text.

China represents the most mature market by far, where the increased dominance of messaging platforms is causing the traditional app market to stall. This trend is continuing to grow, not only among consumers but also among businesses or in the prosumer context.

"We expect AI, machine learning and VPAs to be one of the major strategic battlegrounds from 2017 onwards, and make many mobile apps fade and become subservants of VPAs," said Annette Zimmermann, research director at Gartner.