Ads. It's pretty clear if you read their TOS[1] or Privacy Policy[2]. In particular from the privacy policy:
>Arcode displays targeted advertisements based on personal information. Advertisers (including ad serving companies) may assume that people who interact with, view, or click targeted ads meet the targeting criteria, such as a particular gender, age group and geographic area.
>Arcode displays targeted advertisements based on personal information. Advertisers (including ad serving companies) may assume that people who interact with, view, or click targeted ads meet the targeting criteria, such as a particular gender, age group and geographic area.
[1] http://inky.com/termsofuse.html [2] http://inky.com/privacypolicy.html