AdAge

Mobile advertising is swiftly becoming a two-horse race. According to the latest eMarketer forecast, mobile ad spending worldwide grew by 105% in 2013 and is on pace to expand to $31.5 billion in 2014.

And the two Internet giants, Google and Facebook, are increasingly taking the lion's share -- the pair netted 67% of mobile ad revenues in 2013, up from 58% in 2012.

The current report marks yet another adjustment from the research firm, as mobile ad dollars balloon far faster than expected. The final spending figure of $18 billion is nearly double the firm's estimates from just four months ago. Much of the tweaking is due to Facebook, whose share of net revenues more than tripled, to 18%, in 2013, only its second year in the mobile ad business.

Say hello to the new first screen: your phone. Daily time spent on mobile devices is now outpacing TV in the US for the first time, according a newly-released 2014 AdReaction study from Millward Brown.

Americans now spend 151 minutes per day on smartphones, next to 147 in front of TVs. But the numbers are even greater elsewhere.

In China, consumers spend a whopping 170 minutes a day buried in smartphones, nearly double their TV watching time. Users in Indonesia, the Philippines, Brazil and Vietnam also spend more total screen minutes on average than the US, predominately on mobile. The firm surveyed more than 12,000 mobile users, between the ages of 16 and 44, in 30 different countries, polling consumption of ads over TVs, laptops, smartphones and tablets.