Does iPhone Turn On the Web Beacon?

It's a legitimate question because of how Apple's mobile e-mail application handles remote images. This is one of those I meant to, thought I had, but forgot to topics. Nearly the first question—maybe it was first—I asked Apple during my iPhone 3G briefing in mid-July: Does iPhone's mail client block external images? The answer: No. The justification, which is somewhat reasonable: The mail client initially just downloads headers.

GOT A TIP OR RUMOR?

Yesterday, Macworld UK got around to the topic I neglected in July: iPhone mail security. One of the two concerns: how iPhone handles remote images. The automatic retrieval of images from remote servers lets in Web beacons, which can lead to spam.

A Web beacon is a transparent image, or clear gif, commonly sent out by Web sites. Unlike other images, the user cannot see the clear gif. Web beacons are less onerous than cookies, but are just as useful to site operators for tracking IP addresses and identifying Web browsers and other information, such as accessed content. While clear gifs can be used with cookies, they often don't collect identifiable information.

Reputable companies also often place Web beacons in HTML-formatted e-mail. No surprise, mass marketers and unidentified spammers use clear gifs, too. Web beacons play a more identifiable role when used in HTML-formatted e-mail; opening the message calls up the invisible image from the remote server. In its more sublime form, the Web beacon verifies the e-mail address is valid, but that's enough to set off a torrent of spam. Random and anonymous e-mailers often send out messages to blocks of addresses—many of which won't be legitimate. A Web beacon spotlights which e-mail addresses are good ones.

Before developers like Apple and Microsoft blocked remote images by default, I would get lots of spam. Worst would be the porn spam. I could see a pattern. One message viewed in preview pane would be followed by a torrent of others—and not just from the originating site. In 2002, Microsoft made image blocking a feature of Outlook, which was my e-mail program at the time. Within six months after I turned on image blocking, all porn—and most other—spam stopped.

But would it come back because of the iPhone? That's the question for you. I'm not using the iPhone right now. But when I did use the iPhone, I deleted obvious spam before it could open. Mmmm, maybe my overlooking this topic in July wasn't so bad after all. A few months of real iPhone usage would be best to assess whether or not there is a problem with Apple's approach to mobile mail. So I ask again: Has your amount of spam changed since getting an iPhone? Please answer by e-mail or in comments.

[Please send your tips or rumors to watchtips at gmail.com.]

Posted by Joe Wilcox on October 3, 2008 2:59 PM