A free app for Android, by Team Unfollow.
The Unfollow for Instagram tool allows you to find out who does not follow you back on Instagram. With this, you can track who does not follow you back and unfollow a single user or multiple users at a time.
This app cannot be used for brand marketing and getting more likes and followers. It is very simple to use, and it is designed for both brand and regular users.
This app allows you to track non-followers, so you can unfollow them if you want to.