Advertising companies aren't just tracking your web browsing habits--some marketers secretly monitor your email usage to discover a startling amount of information about you, too.
While senders are limited to only tracking specific messages they've sent to you, doing so can reveal whether you've opened the email or clicked any links in the message. It can also expose your general location and what kind of device you're using.
If you're curious about which messages are monitoring you and which one's aren't, a new extension for Chrome called UglyEmail can help. This extension--by developer Sonny Tulyaganov--monitors your inbox to find messages using pixel tracking. This is a common marketing technique where companies insert a transparent (and therefore invisible to you) one-pixel image into a message.
The pixel image has code in it designed to send back information about you to the company. As soon as you open a message with a pixel tracker in it, the image pings the marketer's servers and the information flow begins. Pixel tracking shows up in all kinds of messages, including newsletters you subscribe to.
Thanks to UglyEmail you can find out when a message has a tracker and decide not to open that email.
Using UglyEmail is simple. Just install the extension from the Chrome Web Store and it should start working. In my tests, it didn't show up until after I'd restarted Chrome, opened a Gmail tab, and then refreshed that same tab.
When it's working, you'll see an eye icon next to the name of the message's sender, as pictured in the image above. This allows you to see at a glance which messages are tracking you.
UglyEmail isn't perfect, however. For starters, it only alerts you to messages with pixel trackers from three companies: Yesware, Bananatag, and Streak. The extension is also a little finicky. If you switch from the Primary tab to the Social tab in your inbox, for example, the UglyEmail icons you saw in the Primary tab will disappear. UglyEmail doesn't work with Google Inbox, either.
UglyEmail also needs permission to "read" your email to be of any use, which is oh, oh so ironic. The good news is Tulyaganov told Wired that any personal data stays on your device and doesn't get stored or transmitted by the extension.
Any performance issues and limitations should improve as development continues on UglyEmail. For now the extension is only for Gmail and only works on Chrome, but a Firefox version is in the works.