There are many services which provide icon sets for purchase, but we recommend the following:
These services provide icon files in a vector format. You'll need to convert them to the color you need (if they're monochromatic icons), and optimally these should be saved as 110x110px PNG files.
Adding icons to your appTo add your own custom icons navigate to Design Phone section of the app builder. Do a mouse over any icon in the menu on the left side and click on the little cog icon.
After you click on the cog icon, the Editing interface will show. You can set a new name for the icon, change the icon itself, or convert it to a separator. To learn more about the separators, click here.
To change the icon, click on the current icon image.
If you'd like to use one of our ShoutEm stock icons, you can select them from the first tab, called Flat. In case you want to upload your own icon, click on the second tab called My Icons.
Under this dialogue you'll see any additional icons you've uploaded. You can click here to upload your own custom icon. After you upload your icons, select any of those icons to use it for the menu item that you are currently editing.
After you select the icon, you can review the icon and the name again. If you are satisfied click on the Save changes button.
Immediately upon saving changes, you will be able to see your new icon inside the application preview screen in the app builder.
Hope this helps!