Follows is an app for the iPhone and iPod touch that can track your popularity and growth across various online services such as Twitter, Facebook, Feedburner etc. It was originally developed for internal use but is now available on the App Store with support for two additional services: Foursquare and SoundCloud.
Use this app to chart how many followers, friends, likes, subscriptions, connections or views you've accumulated across various social networks and services.
You can provide a custom URL to follows and have it track private data such as newsletter subscribers, comment counts, visitors, etc.