Just like every other weekday, I opened up my personal email while riding the shuttle on the way home from work. Unlike every other day, I was met with quite a surprise from both Groupon and Trulia.

It was as if both of them had decided in the last 24 hours to employ new retargeting technology on their websites and mobile apps. Before explaining what I saw in my inbox, I want to first describe how I had used their services.

Casually browsing Groupon’s website

I recently had a bad experience with a Groupon I had purchased for my wife; though, that’s a different story. After requesting a refund via a web form on Groupon’s site, I began perusing various offers.

Among other product categories, I looked up what getaways were on offer in our area. I clicked on several, but there was one in particular that I showed my wife and we chatted about.

I probably didn’t spend more than a few minutes on the page before moving on.

Looking up houses on Trulia’s mobile app

We are planning to move next Spring and so from time to time, I like to take a look at what’s on the market and the current prices.

Bored yesterday, I opened up the Trulia Rentals app on my new iPhone 6 and started looking at places in several of the neighborhoods that we’re interested in.

I didn’t spend a lot of time on the app, but I did add several homes to my favorites list to later show my wife.

Now back to my inbox

Retargeting Email Campaign

When I opened it up, I found four emails in which both companies had used my behavior to retarget me – or serve me an ad based on an action I’d taken – in an attempt to drive further engagement and hopefully additional revenue.

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As you can see, Trulia was very exuberant and sent me three emails about the areas in which the homes that I had saved are located.

What really astounded me, though, was that on Groupon.com, I hadn’t taken any specific action other than to spend a certain amount of time on a page. Groupon then collected that info, put together an ad and sent it to my inbox.

Relevance vs. Privacy

I’ll be honest, the geek and marketer in me loves everything about this. And fortunately for both of these companies, I’m not too squeamish about retargeting or one-to-one marketing.

I love relevance. And if I’m going to be marketed to, I kind of prefer ads that I’m interested in than ads I’m not interested in.

But in light of findings such as Uber admitting to tracking users movements in a really inappropriate way, I become more skeptical. More distrustful. At what point does privacy trump relevancy?

What do you think? Are retargeted ads based on your behaviors relevant or an invasion of privacy?