Google has a harder time seeing her on iPhone.
Facebook has a massive advantage on iPhone that Google does not, I learned from a source in the mobile adtech world at Business Insider's Ignition 2013 conference this week, and this goes some way to explaining Google's sudden insistence that people use Google+ if they want to comment on YouTube videos.
People tend to stay logged in to Facebook on their mobile phones. Not so Google or Google+. So if you're an advertiser and you want to reach people on their phones, the Facebook login identity will be a useful thing. (Facebook is testing a mobile ad network using just this type of targeting right now.)
People stay logged in to Facebook on both iPhone and Android systems, of course. But Google's problems are compounded on iPhone: Because iPhone doesn't have tracking cookies — which help advertisers track your web browsing habits — a lot of Google's search ad products don't work as well on the iPhone as they do on Android or a desktop environment. Cookies are the little bits of software that track your web browsing history so advertisers can target you with ads that seem relevant.
Android does have cookies, and Google can use them to target you with ads when you search for stuff on an Android phone.
None of this is news, of course.
And you'd think that because 81% of smartphones are running Google's Android system, with cookies, that the iPhone gap wouldn't be much of a problem.
But it is.
iPhone users tend to be richer than Android users, and ads running on Apple's mobile devices often have better return on investment.
So one way for Google to develop a target-rich environment for advertisers who want to reach people on iPhone would be for more iPhone users to log in to Google+ and then forget to log out.
By amazing coincidence, Google is now pushing people to log in to Google+ if they want to comment on YouTube videos. One intention here is to "civilize" YouTube, which has become ripe with trolls and bigots who comment anonymously under videos.
But Google also knows that 40% of YouTube's traffic comes from mobile devices, and mobile traffic will only increase over time. A huge portion of those people will forget to log out, and stay logged in semi-permanently, just the way Facebook users do.
That will increase the amount of Google+ logins available for targeting on iPhone — a geography previously ruled by Facebook.
It may already be working. Facebook still dominates social media logins, according to Janrain, a company that tracks social media data. About 45% of logins are from Facebook at any one time in Q3, the company says. But Google+ login were 33% of the audience, Janrain says, and the gap between Facebook and Google+ is closing.
More From Business Insider