Gamers are increasingly turning to their phones to play, changing the landscape of the video game industry.

That's the latest from the analysts at The NPD Group, who say in their new "Gamer Segmentation 2014" report that people who play on multiple systems -- phones, computers and consoles -- grew 6 percentage points over 2013. Those multi-platform gamers account for 22 percent of U.S. video game players.

But the "Free & Mobile Gamers" group is still the biggest, comprising 29 percent of the U.S. gamer population. Other categories of gamers (Casual Gamers, Core Console Gamers, Family Gamers and Social Gamers) declined 1 to 2 percentage points.

So what do the top two groups of gamers have in common? Mobile phones. Seventy-one percent of U.S. gamers have played on their phones, according to NPD Group. It's the only gaming device that saw more use over 2013.

Ok. So people like phone games. But do we spend money on them?

Yes, says NPD. In the past three months, gamers on average spent $16 on digital games, compared to an average of $11 in the same time period in 2013.

Spending is also up on physical games, favored by Core Console Gamers and Family Gamers is also up. People spent an average of $48 in the past three months on physical games compared with $45 in 2013.

NPD also says people are spending more time each week playing games.

"Across both digital and physical formats, spending has increased from last year for consoles, portables, and digital gaming apps, which is great news when also combined with the fact that gamers are spending more time playing games," said Liam Callahan, an industry analyst with NPD Group.