AFS Analytics can display an invisible button or tracker on your website pages. To enable this option, you have to select the option 'invisible button' in the field 'Button displayed on your website' into the 'Edit site info' form. Main menu->Account->Edit site info.
The Invisible button is limited to the first 50,000 page views per month. Once the limit is reached, a small AFS logo will be displayed. This does not affect tracking or analytics reports. You can increase this limit by upgrading your account to silver plan.