The 18-year-old global pop star -- whose fans gave him a social media record for his March 1 birthday -- joined Instagram in July 2011 and reeled in 1,700 followers in just an hour. His inaugural Instagram picture (see below) displayed Los Angeles traffic, with the caption "La traffic sucks."
Bieber has since shared 281 photos and follows 15 Instagram users, including girlfriend Selena Gomez, fellow teen star Jaden Smith and boxer Floyd Mayweather.
Gomez is the second most-followed Instagram user, followed by Taylor Swift and Kim Kardashian.
Previously, Bieber lost the races to 10 million and 20 million Twitter followers, as well as 1 billion YouTube views to social-media powerhouse Lady Gaga. He's in luck this time, however; Gaga isn't on Instagram.
Musicians on Facebook have experienced similarly explosive growth on Facebook, first via fan pages and now on their personal pages thanks to the network's Subscribe button.
Bieber currently has 18.6 million Twitter followers and 41.5 million Facebook "Likes." His official YouTube channel has 2.3 billion views.
Instagram, an iPhone app that has been downloaded 27 million times, announced at South by Southwest this month that an Android version of the app will be released "very soon." Apple also dubbed Instagram its App of the Year in 2011, and company founder Kevin Systrom appeared in Best Buy's Super Bowl ad.
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