I noticed in my app's settings a field called "Preferences URL".
What is it used for?
If your app has a preferences or settings page, enter the url of that page in this field and I believe it shows up in the admin under the app. Here's what it looks like:
I see. I wasn't aware of that.
Not too sure why I would use this though.
It seems to me it could be accomplished by simply having a Preferences page within the app itself?
It's all up to preference (no pun intended). Having a link to a preference page within the app itself is also an option.
I see. Thanks
When you add the "Preferences URL" to your app setup page it adds a button for the merchant to "Edit preferences."
This is what the merchant will see if they go to the About page from Shopify Admin > Apps > Your app: