CloudSponge

CloudSponge helps your business grow faster. Their products will deliver a dramatic improvement the performance of your existing referral features. Stop making your users type their friends'​ email addresses into your referral form, use CloudSponge instead. CloudSponge imports address books from Yahoo, Hotmail, MSN, Gmail, AOL, Outlook and Mac OS X Address Book. Use these addresses to Invite Friends, Find Friends, or whatever application you need.