here. Adf.ly offers their greatest feature such as real-time demographic visitor count, mass shrink links to shorten multiple links for the same time, if you have many links you can use this feature maximum for 20 links to shorten. They also have referral programs, where you can earn 20% from every links that click own by your referrals. You can see and learn more of their features on adf.ly sites.
If you interested with Adf.ly rates or the features on the site, you can register for free here!