Instagram co-founders Kevin Systrom and Mike Krieger have officially resigned and are set to leave the company in the coming weeks. They both stated that they wanted to take some time off and explore other projects. They both launched the photo and video sharing app in 2010. Facebook acquired it in 2012 for $1 billion when it only had 30 million users. Today, Instagram has more than 500 million users and estimated to be worth more than $100 billion if it were a stand-alone company.