Erica Sadun:

Apple’s new App Clip technology lets people load transient mini-apps without installing through the App Store. Users don’t have to authenticate or authorize the mini-app. It just downloads and works. Whether scanning a code (think QR code) or detecting an NFC tag, iOS users can download and run these pre-vetted packages that represent a light, typically transactional, view of a larger app experience. I went through some writeups and video today and thought I’d share a mental dump of my thoughts.

App Clips are designed for transaction. As an app, rather than a web page, they integrate seamlessly with the store ecosystem, allowing users to purchase goods and services from an instant menu and integrate with features like Apple Pay.

Honestly, there’s nothing an App Clip can do (maybe other than something like Apple Pay) that a reasonably designed web page cannot but it’s that charm and an eye towards lowering the transaction barrier that makes the Clips so compelling. With Clips, end-users can point, pick, and pay with an absolute minimum of effort.

Short but good description of the possibilities of App Clips.