>But trying to drill down into specific definitions or draw a clear line between them seems to fall apart quickly.
The only clear line I've seen is javascript. If it uses javascript for anything nontrivial, people believe it's a web app. This comes up all the time in threads about "the old web" or "how you would fix the web," in the context of what seems to be a prevalent belief on HN that the web should be split up between the two paradigms, with purely static, noninteractive "sites" in one place, and "apps" in the other.
Problem is, as mentioned upthread, the vast majority of sites using javascript, including SPAs, are still meant to be read as documents. If you include any form of interactivity, including backend processing and rendering, even more sites become apps.
In practice, it seems to me to be more of a religious taxonomy than a technical one, based on the belief that the modern web has become tainted by complexity and needs to be made pure again.
> In practice, it seems to me to be more of a religious taxonomy than a technical one, based on the belief that the modern web has become tainted by complexity and needs to be made pure again.
I see it more being whether a page uses progressive enhancement. If I can disable JavaScript and at least be able to read a page's content, then its a web page rather than an app. If JavaScript is an absolute requirement for any functionality it's an app.
A page with some client-side form validation, AJAX submissions, or even just some dynamic content are awesome uses of JavaScript so long as the pages themselves don't hinge on me running the JavaScript. Posting a comment might be a POST and clicking an image thumbnail might load it in a new tab instead of a light box. The functionality is all still there if for any reason the JavaScript doesn't load.
One of my big problems with "apps" is they have zero provisions for JavaScript not running. Most "apps" don't even give an error page telling you explicitly JavaScript is required. Even when you have JavaScript enabled they tend to break in stupid ways if you've got an ad blocker.
The only clear line I've seen is javascript. If it uses javascript for anything nontrivial, people believe it's a web app. This comes up all the time in threads about "the old web" or "how you would fix the web," in the context of what seems to be a prevalent belief on HN that the web should be split up between the two paradigms, with purely static, noninteractive "sites" in one place, and "apps" in the other.
Problem is, as mentioned upthread, the vast majority of sites using javascript, including SPAs, are still meant to be read as documents. If you include any form of interactivity, including backend processing and rendering, even more sites become apps.
In practice, it seems to me to be more of a religious taxonomy than a technical one, based on the belief that the modern web has become tainted by complexity and needs to be made pure again.