FanScan

FanScan is an app that shows which of your Instagram followers is your biggest fan. With this app, you can see a ranking of the users who follow your activity on a regular basis and mark your photos as favorites.

In addition to showing you the most active followers for your account, FanScan also lets you manage your account as you would from the official Instagram app. With this app, you can follow, unfollow, favorite photos, leave comments, see your TL, or even search for tags and users. You can do this all from one interface with hundreds of backgrounds that you can use to customize it.

FanScan also lets you browse other accounts, so you can see who's the biggest fan of other people, too. You can view the 10 most active followers of any Instagram account as long as it's not private.

FanScan shows results based on how many times a person has interacted with your photos on Instagram. So, no matter how recently they've favorited something or commented, it will add up. As time passes, your top followers may change, so you can use this app to make sure you always know who's your number one fan.