Instagram Is The Fastest-Growing Social Site Globally, Mobile Devices Rule Over PCs for access by Ingrid Lunden

Pinterest may have passed Twitter in popularity in the U.S. according to new figures out last month from Pew, but globally the social network to watch may be Facebook-owned Instagram. According to research published today by the GlobalWebIndex, Instagram is growing the fastest of all social media sites worldwide, increasing its active user base by 23% in the last six months.

But on an overall basis, it’s still behind the likes of Facebook, YouTube, Google+, Twitter and LinkedIn — which come respectively in at positions 1-5 of the world’s most popular social platforms in terms of penetration.