> ## Knowledge Base Index > Fetch the complete knowledge base index at: https://help.smartxaas.io/sitemap.xml > Use this file to discover available pages before exploring further. > Pure-Markdown content can be obtained by appending a '.md' suffix to the content URLs listed in the sitemap (without the trailing slash). # List of Macros / Placeholders available apart from {click_id} [Open in Zendesk](https://smartxaas.zendesk.com/hc/en-us/articles/360026061891) | --- We are able to pass some additional macros/placeholders apart from**{click\_id},**which can be replaced with corresponding values and passed via tracking or a redirect link.
We currently support only two additional macros that we populate on click-out:
-**{gaid}**- google advertising id -**{idfa}**- apple advertising id -**{pub\_id}**- first-level publisher ID -**{sub\_id}**- second-level publisher ID (if available)**Example:**_https://example.com/tracking.php?campaign\_id=XXXX&click\_id=**{click\_id}**&gaid=**{gaid}**&pub\_id=**{pub\_id}**&sub\_id=**{sub\_id}**_
You can use those to assign installs / in-app activity to specific publishers or sub-publishers and thus optimize campaign performance over time by eventually blacklisting non-performing sources.**NOTICE- We have migrated to GitBook:-**[List of Macros / Placeholders available apart from {click\_id}](https://docs.smartxaas.io/cpidroid/advertiser/images-and-media/tracking/list-of-macros-placeholders-available-apart-from-click_id)