Web vs. Desktop Applications: The Neverending Debate

Imagine something like POSIX but much more extended, covering APIs for GUI, database access and so forth (basically what the Java VM provides), the "Application Browser" can just be an url in the form app://foobar.com/email.app that will run as native application. Still it can be a server-side application where all your data is saved server-side, and of course the environment can be smart enough to automatically download and install a new version of the program when available (actually the local copy can be just a caching business).

The web is going to offer all this in the end, but currently it's ridiculous stupid compared to a real environment. You can't do free networking, for instance, things like opening a socket and sending/receiving data using a non-HTTP protocol. In the end the web will provide all the stuff that now are trivially done in the desktop side, but my feeling is that this was the wrong path since everything is already here, the technology and decades of desktop applications capable of doing very smart things.

We are reinventing the wheel using the wrong foundation (HTML+CSS for GUIs, GET requests for all the kind of networking, ...).

It's also a shining example of many of the things that are wrong with downloadable software, though some of that is this particular incarnation (the app store) more than the whole idea.

There's no argument to be made that all computation should be done on the server and just rendered on the client. That model is on the way out for web applications (not to be confused with web sites). I happen to think Cappuccino is going in a great direction ;-)

Sure, "we" know that a Prism "app" is really just a web app running inside of a stripped-down copy of Firefox, but the average person (who makes the market) doesn't know that. I've set up some non-technical friends with a copy of Firefox, as well as three or four Prism "apps" - Gmail, Google reader, NYT.com, etc. They don't know, nor do they care, that they're using web apps: they interact with them as desktop apps, which is what matters to them (despite the fact that I've explained to them what's going on).

The really interesting thing is that they distinguish between the Gmail they get by typing the URL into Firefox, and the Gmail they get by launching the Prism "app". Despite the interfaces being 100% identical, they still think of the Firefox-based one as the "web version" of it, in the same way that Outlook users see OWL as the "web version" of normal Outlook - doesn't matter that they're the exact same.

As for web vs. desktop, I think - like most things - it's a case where different tools have different strong points. Some apps will naturally work better in a web-based environment, but some will stay desktop-based.

Seeing as I have as little idea about the future as everyone else does, I'll offer two predictions about the two sides coming together:

In the shorter-term, we will see more desktop apps accessing web services behind the scenes. The main application will still be desktop-based, but some resources (or more likely, improvements on native resources) will come from web services. The big example of this, currently, is Mathematica's cloud computing initiative. To the user, Mathematica is Mathematica - it's on a desktop client, and it's as responsive as ever. But you can configure this desktop client to (silently) spin up an EC2 instance with the Mathematica engine pre-loaded onto it, and route complex calculations to that more-powerful instance, as opposed to computing it locally. To the user, there's no visible difference between locally-computed answers and remote ones; but the desktop app has chosen which source to use based on the calculation.

In the longer-term, the distinction between desktop apps and web apps will disappear. What makes something a web app? Currently, it's that it's written in Javascript that's downloaded and executed in a browser context. What about when browsers have more powerful languages built-in (like Google NaCl promises), and can access the hardware more directly? What about when your OS comes with a built-in ability to download and run these programs, without explicitly invoking a browser - your browser is conceptually like a VM for Javascript, so when this VM is integrated directly into the OS (like Java), what is it?

Let's say I've got a copy of Gmail that uses Gears for persistence, some NaCl to offload some of the processing, and is accessed via a Prism instance - is this a web app or a desktop app?