"While the icon is a colorful doorway into the Instagram app, once inside the app, we believe the color should come directly from the community's photos and videos," wrote Instagram's head of design, Ian Spalter. "We stripped the color and noise from surfaces where people's content should take center stage, and boosted color on other surfaces like sign up flows and home screens."
I don't have access to the newer app yet, but the redesign looks like an intriguing one for Instagram. It hasn't done much to tweak the look of its apps for the past five years, so it makes sense for it to take some big leaps now. The black and white design feels much more mature, instead of something from a small startup that inexplicably became a giant social network.