What is Apple App Clip?
iOS 14 adds new App Clip feature to easily access applications quickly without downloading the full version from the App Store. The App Store is adding support for app previews called App Clips, enabling users to grab mini or demo versions of key app content without the need to download the full apps. The main purpose is to provide a better promotional opportunity for software, as well as quick access to purchasing, ride-sharing, or rental apps. The user can launch an App Clip for just a single purpose, such as making an Apple Pay purchase quickly from a web link, or a QR code, or an NFC tag. New Apple-designed App Clip codes will include support for NFC and QR-style scanning. Clips will be 10MB or less in size, and one app can have multiple App Clips, such as Yelp support for restaurant-specific clips.
Take a deeper look at Apple App Clip on Apple Website: Link