It became the fourth Facebook platform to eclipse the billion-user mark, including the namesake social network with more than two billion users, and the messaging applications WhatsApp and Messenger.
Zuckerberg issued a public statement about the departure saying that he had enjoyed working with Systrom and Krieger. Its user base has since climbed to one billion.
Facebook's shares were down 2.4% at $161.51 in early trading yesterday, knocking more than $11bn off the stock's market value.
Instagram co-founders Systrom and Krieger leaving firm
He added: "Building new things requires that we step..."
Adam Mosseri, who had been in charge of your favorite feature of Facebook (News Feed!), recently became Instagram's head of product. Zuckerberg ally Chris Cox, who leads product development for Facebook's main app, gained oversight of WhatsApp and Instagram, which had been given independence when Facebook bought them. Crucially, Instagram is popular with teens and young people, a demographic Facebook has had trouble keeping. But in the six years they've continued at Instagram post-acquisition, they have built a money-making giant.
"We're planning on taking some time off to explore our curiosity and creativity again", Krieger wrote.
In a statement, Zuckerberg praised Instagram's founders.
Even before we got to this point, Instagram was already becoming a vastly more crucial piece of the Facebook portfolio of companies and services. Those trends reversed in July, when the company sent tremors through the stock market by warning that its growth was slowing, an announcement that chopped nearly $120 billion from the firm's market value. However, in recent months Zuckerberg begun to take a more hands on approach as the photo-sharing app soared in popularity while Facebook, marred by various scandals, struggled to attract new users. Concerns over Facebook's business sparked the biggest one-day wipeout in U.S. stock market history in July.
Instagram is its parent's fastest-growing slice of revenue, but it touts 4 million fewer monthly advertisers globally.
No-deal Brexit could ends UK-EU flights, government says
However, any post-Brexit immigration policy could be affected by Britain's future trade deals. He told Sky News: "We will vote against (a deal) if it doesn't meet our six tests".