With more than a billion users as of June, Instagram has also been a growing source of revenue, likely to bring in more than $10 billion from advertising by 2019, according to the research firm eMarketer.
Instagram has been one of Facebook's most successful acquisitions.
The company has started mentioning Instagram more frequently on its earnings calls and taking credit for its success.
He added: "Building new things requires that we step..."
Founders Kevin Systrom, who served as chief executive, and Mike Krieger, the chief technical officer, tapped into the social network's vast ad platform and sales force to help their creation flourish without being associated with the larger machine.
Kirk expected to move more quickly west through ocean
Tropical Depression Kirk is several hundred miles west-southwest of the Cabo Verde Islands, with maximum winds of 35 mph. Kirk is expected to move west toward the Caribbean Ocean over the next several days.
All of this said, hopefully Kevin and Mike's departure doesn't foreshadow an increasing Facebookification of Instagram.
Systrom's fortune is valued at $1.4 billion by Forbes.
"The challenge with Instagram has always been balancing its strong desire for independence, with the need to make Instagram a part of the Facebook machine", said eMarketer analyst Debra Aho Williamson. The departure of the Instagram co-founders comes months after the exit of Jan Koum, co-founder of WhatsApp (which was bought by Facebook in 2014) following disagreements over user privacy and the end-to-end encryption the service uses.
Instagram is one of Facebook's most important properties and recently hit a reported one billion users.
Systrom, 34, and Krieger, 32, informed the photo-sharing app's leadership team and Facebook of their decision on Monday. Apple and Amazon are two of the most heavily weighted stocks in the United States market.
Earlier in September, the European Union called Facebook to explain what it does with its users' personal data and how it shares their information with third parties. One distinction is that the WhatsApp disputes centered on the debate over whether to allow ads within the messaging service, which the co-founders had long opposed, whereas Instagram embraced ads early on.
All of this proves that Instagram is hugely important to Facebook's future growth, not least because the brand is still comparatively untainted.