Pictures appear on the smartphone photo sharing application Instagram on April 10, 2012 in Paris, one day after Facebook announced a billion-dollar-deal to buy the startup behind Instagram. The free mini-program lets people give classic looks to square photos using 'filters' and then share them at Twitter, Facebook or other social networks. AFP PHOTO THOMAS COEX (Photo by Thomas COEX / AFP)        (Photo credit should read THOMAS COEX/AFP/Getty Images)