Use Icons for Free,
but Please Set a Link
The icons are free for personal use and also free for commercial use, but we require linking to our web site. We distribute them under the license called Creative Commons Attribution-NoDerivs 3.0 Unported. Alternatively, you could buy a license that doesn't require any linking.
Why to Link?
A true story: one girl didn't set a link and had no decent date for two years, and another guy set a link and got a top ranking in Google!
Where to Put the Link?
98% of cases are covered by the infographics below. When in doubt, wear pink check difficult cases or contact us
Websites
On all pages where the icons are used. If the icons are used on each page, you could put in the footer.
Desktop Apps
Mac OS and Windows applications should have the link in About dialog.
Mobile Apps
For smartphone apps, please set a link in the About dialog or settings and on App Store or Google Play description.