If all you want is the tracking and ad blocking, DNTM works well enough behind the scenes. Once you click through to the Tracking area of the options window, you'll see a list of the trackers blocked for that site — with the option to turn off blocking for individual trackers or the entire site.
Then there's a link to the Tracking Dashboard, which opens in a new tab and shows a graph with the total number of trackers blocked over the past 10 days. Interesting info, but I feel that it should have been integrated into the tool rather than requiring a visit to a whole new tab.
I briefly tested the other features, such as password management, and they worked as advertised.
Bottom line: Though a capable ad- and tracker-blocker with some nice extras, DoNotTrackMe feels unnecessarily complex. Even so, the credit-card alias option makes a strong case for subscribing to Premium.
Price: Free; supported by optional "donation" of tracked data
Compatible with: Chrome, Firefox, Opera, Safari
Ghosts can't be seen, and Ghostery aims to lend you that kind of invisibility when you venture onto the Web, drawing on what the developers claim to be the Web's largest tracker database. It costs nothing, not even a donation, but Ghostery does engage in some optional, anonymous data-mining: Its opt-in Ghostrank feature collects data about the browser you use, sites you visit, trackers you've encountered, etc.
What it does: Right out of the box, Ghostery blocks tracking cookies and scripts. Within its settings, however, you'll find a number of additional blocking options: advertising, analytics, beacons, privacy and widgets. Within those categories, you can opt to block some, all or none of what Ghostery finds.
How it performed: Ghostery makes a good first impression with a helpful tutorial that appears the first time you click its toolbar icon. The second impression? Less good: By default, an ugly purple box appears as it identifies trackers on each site you visit. You can turn this off, but it's an unwelcome, unnecessary distraction that shouldn't be on to begin with.
Like most of the other blockers, Ghostery displays a numerical blocked-items counter in its toolbar icon, a click of which reveals the plug-in's full menu. That menu consists of a scrolling list of trackers, each with a brief description of what it is (advertising, analytics, etc.) and an on/off toggle. This makes for very easy customization for any given site and helps you learn how different elements can affect what you're seeing.
For example, if you know a particular site uses Livefyre for its comment system, and you suddenly find the comment window has disappeared, it's a simple matter to toggle off the Livefyre blocking from within Ghostery's drop-down menu.
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