The only benefits I can see of "Apps", are the developer get's access to private information they really don't need.
Yeah, they get to be on the "App Store". But the "App Store" is a totally unnecessary concept introduced by Apple/Google so they could scrape a huge percentage in sales.
Web browsers have good (not perfect) sandboxing, costs no fees to "submit" and are accessible to everyone on every phone.
Also, this situation benefits the google-apple duopoly, since it means superior products (remember Windows Phone 8?) or privacy focused devices (FirefoxOS) have no chance of getting a foothold in the marketplace.
The objections I see in sibling comments are nonsense. Modern web supports high frame rates, developer control over the UI, etc, etc.