The core problem was that deep links only really worked if a user already had the app. Because the average phone has fewer than 100 apps installed, and the same apps dominate most phones in the market, deep links were useless for almost every app in the app stores.
Recently, a new type of deep linking has appeared. Contextual deep-linking technology offersdeep links that can pass data to an app through install, in addition to supporting the legacydeep-linking method.
This data is used by the app to show the user relevant information when they open the app for the first time (below). This makes deep links useful for users who didn’t have the app, as well as those who already did. Now, deep links work for newly acquired users, not just existing users, driving growth and re-engagement.

Providing context prior to and after install of an app is crucial to new user signup and retention. Haven't found many, if any retailers using contextual deep links.