More than 268 billion app downloads will have been made by 2017, with mobile users providing “personalised data streams” to more than 100 apps and services every day, according to analyst firm Gartner.

Brian Blau, research director for the company, said mobile apps have become “the official channel to drive content and services to consumers” meaning users are constantly “funnelling” data — such as comments, activity and location — through mobile apps.

With free apps in particular, users are increasingly accepting advertising or connectivity to their data in exchange for the functionality provided by the apps.

The analyst firm predicts mobile apps will increase in importance as the use of mobile devices and wearable technology move into new areas.

Gartner predicts wearable devices will account for 50 per cent of app interactions by 2017, as their limited user interfaces means they rely on apps on smartphones for much user input and output, configuration, content creation, consumption and connectivity.

“While wearable devices will not fully rely on, or be a slave to, mobile devices, it is a way for manufacturers to keep these devices small and efficient, therefore significantly reducing device costs in favour of using apps, which are more easily maintained and updated,” said Blau.

The level of activity in mobile apps will mean the sector will have generated $77 billion in revenue by 2017, Gartner forecast.

The way in which apps make use of personal data has been the cause of some concern.

The UK Information Commissioner’s Office recently said developers should follow a “privacy by design” approach when building apps to address consumer concerns and comply with data protection laws.