They have a beautiful digital magazine that doesn't need to live in a native app -- and had no compelling reason to.
When we started building our smart news app ( more info at https://recent.io/ ) we considered creating a non-native web app and took a few steps in that direction. But we rely on touch gestures a lot, require no keyboard input except for searching, update news recommendations minute-by-minute, and wanted to appear in the app stores, so we went down the iOS and Android paths instead.