IGBlade - Free instagram analytics and email reports.
StatFlux - Instagram User Analytics and Performance Reports
Inspect Social - The easiest way to track your social media statistics
SocialBlade - SocialBlade can help you track YouTube Channel Statistics, Twitch User Stats, Instagram Stats, and much more! You can compare yourself to other users and analyze your growth!
AuditUser.com - Instagram User Analytics
GramStatistics.com - Explore Instagram user statistics and activity.