Instagram sorts any user's following list order by default based on mutual interaction. It means the accounts that users interact with the most by liking their posts, tagging them in stories, and engaging via direct messages and comments will appear at the top of the following list.

The app was launched in 2010 by cofounders Kevin Systrom and Mike Krieger, and it is now owned by Meta Platforms, Inc., the parent company of Facebook. One of the biggest social media platforms in the world, Instagram surpassed two billion monthly active users in 2022.

Adam Mosseri (@mosseri)

Meta, the company that owns Facebook, also owns Instagram and WhatsApp, two other extremely popular social media platforms. The company has made many acquisitions over its history, including Onavo, which became Facebook Israel, and Belgua, which became Facebook's Messenger app.