One of the great things about desktop software, and mobile apps, is that once you have some software, if you don’t do anything it generally just keeps working. Now there are exceptions to this – if you live in the iOS gilded cage, your cojones and your apps still belong to Apple, and they can yank them any time they like. But they don’t do that all that often. And if your app requires network interactions, perhaps the thing it interacts with will change, requiring an app update. But generally speaking, if I get a text editor app, it’ll still be able to edit text until my phone dies or I delete it. And that gives me a great sense of confidence and stability in my use of my technology.
The same is not true of web pages. They can go away at any time. As can cached copies, archive.org copies, or whatever.
So, as we build Firefox OS, and the line between apps and websites gets blurred, let’s make sure we don’t lose this feature. Once the user’s mental model of what’s going on suggests to them that an app is “theirs” (and that doesn’t just mean “they paid for it”), then we need to make sure that it just keeps working. Even if the original source goes offline.