The average time Americans spend playing games on mobile devices has gone up by 57 per cent in the past 2 years, from one hour and 20 minutes per day in 2012 to over two hours in 2014, according to a report from NPD Group.

Perhaps unsurprisingly, children ages 2 to twelve spend  the greatest proportion of their device time on gaming versus other activities. The average number of playing sessions peaks among “tweens”, then falls through the teenage and early adult years.

The study also revealed that the growth of the tablet market, as well as continued improvement of technology, has seen these devices in particular become central to mobile gaming.

Tablet gamers are also more likely to pay and spend more money on average than other mobile users.

Liam Callahan, industry analyst at NPD Group, expects the trend to carry on: “Continued mobile growth will stem from existing customers paying more to play, especially in the free-to-play portion of the market.

“A positive sign of consumer behaviour trending this way is the fact that more than twice the number of app gamers reported making an in-game purchase than they did when we conducted this study two years ago.”

Adult gamers spend more than children and teenagers, partly because they are often the decision-makers for their young children’s gaming experiences, making them a prime target for developers and marketers, the study notes.

Time spent playing games on console and computers is about the same as a year ago, showing that mobile has not diminished the popularity of traditional gaming devices.