• by Mark Walsh  @markfwal, September 5, 2013

More than half of all time spent online is now through a mobile device, according to a new study by comScore and mobile ad network Jumptap. Of the 51% of online time spent in mobile, 39% is on smartphones, and 12% on tablets.

The report also pointed out that widespread adoption of mobile devices has nearly doubled the total amount of time spent online over the last three years, climbing to 8,908 minutes in February 2013 from 4,518 minutes in February 2010.

Tablet ownership is growing the fastest, up 59% in the year ending April 2013, compared to 22% for smartphones and 1% for PCs.

If most Americans are now dividing their time between the desktop and mobile devices, the research pointed out some differences in usage among key demographic groups. Women ages 25-49, for instance, are most likely to be mobile-only users, with 14% eschewing PCs altogether. By contrast, people 50+ are mostly likely to be desktop-only users (40%), while men 25-49 are the biggest cross-platform users (74%).

The rise in monthly hours spent on smartphones has increased the most among those 18-24, increasing 40% between October 2012 and April 2013. It went up by about a third for women 25-49 and people over 50.

The type of device people use also varies by content. The bulk of music streaming (77%) takes place on smartphones, along with checking the weather (55%), and almost half the time (48%) spent playing games. The PC tends to be the screen of choice when it comes to business and finance, sports, and food-related sites.

Tablets account for about a third (34%) time people spend playing games, 15% of music streaming and 16% of time on food sites.

Looking at device activity by time of day, smartphone and tablet use peaked during prime time, while PCs dominated during the workday before they tailed off at night. The study highlighted behavior related to weather content. Activity spikes in the morning across screens before falling into a familiar pattern of steadier use throughout the day on smartphones, PC use peaking in the daytime, and tablets ruling the night.