John Gruber, "Native Apps Are Part of the Web":
Users love apps, developers love apps — the only people who don’t love apps are pundits who don’t understand that apps aren’t really in opposition to the open Internet. They’re just superior clients to open Internet services. Instagram didn’t even have a web interface for years, but native app clients for iOS and Android didn’t lock Instagram into anything. Their back-end is just as open as it would have been if they had only had a web browser client interface. They just wouldn’t have gotten popular.
It’s just a conceptual simplification. Instead of a web app running inside a browser running as an app inside an OS (three levels of abstraction), we just have apps running within an OS (two levels). Simpler, easier, more elegant. While, as Gruber rightly points out, there are plenty of good (even great) Web apps --- I would cite what Apple's done with iCloud.com as a good example --- the truth is that native apps are part of the same Internet. It's just that, I think, native apps offer superior experiences and functionality --- and in this mobile-first, always-on-the-go world of ours, experience is what really matters.