Confirm there are not already settings or features that do what the shop is asking for:

Confirmed. While CommentSold supports Universal Links (standard https://borntoglam.commentsold.com/products/id/6892 links that route to the app), there is currently no shop-facing setting or documentation that provides the raw, custom native app URI scheme (e.g., borntoglamcommentsold://products/id/6892 ) tailored for individual white-labeled apps.

What does the shop want the product to do?

The shop wants us to provide the specific custom URL scheme format (the native deep-link URI) for their specific white-labeled mobile app ("Born To Glam"). They want to be able to manually construct links formatted like borntoglamcommentsold://products/id/6892 so they can force-open specific product pages directly inside the installed native app, bypassing universal web links entirely.

Why/how would it improve sales or efficiency?

Providing the custom URI scheme allows the merchant to create high-converting, friction-free marketing campaigns (such as SMS, specific email clients, or social media ads) where standard Universal Links sometimes fail or route users to a mobile browser instead of the app. By forcing the native app to open directly to the exact product page, the shop removes unnecessary clicks and login hurdles, providing a seamless user experience that directly increases conversion rates and mobile app sales.