Instagram overtakes Twitter: What you need to know
Who's bigger Twitter or Instagram?
That's an interesting one because Instagram now claims to be the biggest of the two with more than 300 million people around the world reckoned to be using the photo-based network.
What about Twitter?
Well, in July Twitter said it had 271 million active users. However, Facebook claims to have 864 million daily active users, making it by far the biggest social network.
What did Instagram say?
Boss Kevin Systrom said: "Over the past four years, what began as two friends with a dream has grown into a global community that shares more than 70 million photos and videos each day."
Who owns it?
It was bought by Facebook for $1bn more than two years ago. The deal netted Systrom an estimated $400m. Co-founder Mike Krieger earnt around $100m. Systrom had turned down an offer from Mark Zuckerberg's offer to join the Facebook team in 2004 before it made it big.
So Facebook clearly hasn't ruined it?
Not according to the latest figures. Mind you, at the time of the deal, Zuckerburg promised to build on Instagram's existing features rather than simply integrate them into Facebook. He also promised to keep it as an independent program so it could be used on social networks like Twitter.
What else does Facebook own?
It bought WhatsApp for $19bn.