do not step out
rookie play
06/Mar/2007 | 19:33

Overreaching: Internet-enabled Disk Images

I'd like to take a moment to lay down why Apple's "Internet-enabled" disk images are a pretty bad piece of user experience. First, a short explanation of what they are:

When you build a disk image with the command-line hdiutil tool, you can choose to "Internet-enable" the image file. Upon mounting, the image copies its contents to the folder containing the disk image. The image then unmounts its volume and deletes itself automatically.

Apple's got great human interface people, but they're not perfect, and I think they've got this one quite wrong. Let's explore.

Peanuts and Cracker Jacks

1. When you put in a CD and open the icon, does it install your program on the Desktop and eject itself? No? Score card:

Internet-enabled images: 0.

2. When you double-click a zip file on the Desktop and an app appears, does the zip file delete itself? No?

Internet-enabled images: 0.

3. If you back up software you download, which isn't a bad idea necessarily, an Internet-enabled disk image kicks a bucket of suck all over your plans. Before you double-click the image and it does its thing, it just looks like . . . a disk image. Inconsistent behaviour that results in deleting stuff people might want. Argh.

Internet-enabled images: 0.

4. Sometimes, users want to install software on a different computer than the one that downloaded it, but they check it out before migrating the disk image file and performing the permanent installation. Skynet-enabled Internet-enabled disk images force the user to download the software again in such an event. Essentially, this is a corollary of #3 that occurs when there's no way to know that new download of yours is plotting to destroy itself.

Internet-enabled images: 0.

5. When Software Update downloads the latest iTunes update and installs it for you in the background, you never see the temporary package. It's buried--out of sight. Disk images you download from Web sites aren't like that. Users have an expectation that when they see something on their Desktop, it's not a temp file that the computer is going to remove automatically. I downloaded it by clicking on a link, I saw Safari say it downloaded to my Desktop, I see it next to my HD icon, it's "my" data.

Internet-enabled images: 0.

6. Let's say by some magical psychic ability, you know the disk image going to delete itself like some Mission: Impossible dossier, so you back it up before using it. Now there's a new problem: EVERY TIME you go to use the image from my backup, the image is going to delete itself, so you have to remember to back it up every time. BOOOO-urns.

Internet-enabled images: 0.

John Madden, Where Art Thou?

With no points on the board, the Internet-enabled disk image doesn't get to the playoffs, and probably should get kicked out of the league.

To the user, a file is a document is an item is an object is a thing. You click on it and then, um, Stuff Happens™. When Mom and Dad click on Word files, the files don't vanish, for example. They will not assume nor expect the zip file next to the Word file to vanish immediately. Data with a mind of its own is unsettling and potentially frustrating for many, many users.

The problem of course is that, as Finlay Dobbie puts it:

"[T]he issue here is that users find the whole concept of a file which appears on the desktop like a disk to be fairly confounding."

He's right.

Internet-enabled disk images attempt to simplify a rather abstract concept for the user. That's Good™. We like that. The opacity of the behaviour, however, raises several points of further confusion and frustration for people.

It's great to make things easier on users, but Apple hasn't convinced me that this feature improves the overall user experience enough that it outweighs the significant problems presented by it.