A link to an order can open it directly in an app. If the link is a normal web address, it can also open a web page when the app is unavailable. When set up to open an app, this is called a universal link on Apple devices or an app link on Android. A custom URL scheme instead uses a special app address that cannot open a normal web page.

A deferred deep link aims to take someone to that same place after they install the app.

If an item is missing, an invitation has expired, or someone needs to sign in, the app should explain what to do. A link must not give someone access they would not otherwise have. A normal web address can provide a backup when the app cannot open.