None of the things you've listed are actually really problems, or have well-known solutions. HTTP caching solves the downloading problem for most classes of app

None of the things you've listed are actually really problems, or have well-known solutions. HTTP caching solves the downloading problem for most classes of application. You can also run apps locally with app-cache and local storage (and in the future IndexedDB), though I'll grant that this isn't absolutely perfect today. I don't understand your "installation" issue. A user with NoScript knows how to turn it off for a web application they want to use, and generally do so. They just want to retain control over JS execution. AdBlock is not related to actual application delivery, but revenue generation, somewhat orthogonal. Having to support cross-platform quirks is also something that isn't unique to the web. If you support multiple versions of iOS for your app, you will hit similar issues. Not to mention if you wanted to actually be cross-platform and work anywhere other than iOS with the same app.