The rise of mobile technology has opened a world of possibilities for advertisers — one where real-time and hyper-local data makes it easier to serve ads that are more relevant and gain more tangible offline attribution metrics. Much of that data is gathered through public interaction, whether it’s from a wi-fi check-in at a store or simply from a digital billboard as people walk by.

But the wonders of technology aside, how much is too much for consumers? Do advertisers and agencies still have a perception problem to work against? And what should those advertisers stay away from to avoid turning consumers off all together? The issue came to light last month when the CBC published a story on one woman’s reaction to being served ads after signing up for free wi-fi.

How can advertisers avoid coming off as Big Brother-esque, and what do they risk when getting too personal with their audience?

Ernie Simon, CEO of Mindshare North America, said advertisers first need to know that different groups and generations have varying ideas of what is “too personal.”

With millennials, he said, the group is usually open if some sort of explanation is given.

“[Millennials] tend to be hyper-sensitive to the feeling that they’re being tracked,” he told MiC. “But once you tell them why they’re being tracked, they tend to understand the exchange.”

Also, a 2016 study by the Digital Advertising Alliance of Canada shows that the younger gen are typically more aware of consumer tracking and the benefits of ads: while 53% of overall survey respondents understood that ads support free services and 65% recognized that data is collected about them online, millennial respondents over-indexed against the average. For the 18 to 34 crowd, 68% understood that ads support free services and 71% knew that data was collected about them online.

Simon said older audiences have misconceptions regarding targeting. “Older folks who have maybe seen Minority Report too many times, they’re not going to be comfortable knowing that someone has access to that much data.”

There are instances in which laws have actually been broken — Canada’s Personal Information Protection and Electronic Documents Act specifies that advertising should not be targeted using personal data deemed as “sensitive,” such as a person’s health. However, Google was found to be in violation of that law in 2014 when the Office of the Privacy Commissioner of Canada found that the company had targeted a man based on his health conditions, data it had gathered from his purchase history.

But Simon said even when it’s legal, with the average mobile ad served collecting 150 data points, it is still very easy to get into the creepy territory, or at least to be perceived that way. For example, he said, if someone is watching television while scrolling through social media on their phone and they see an ad for toothpaste on TV and then promptly served with an ad from a competing brand on mobile, it’s perfectly understandable to feel like it’s too personal.

“You want to find an ad that complements the situation. Whether that is more specific or more general will depend on your audience, but making people feel like they’re being watched is never a solid strategy.”

Simon said that the risk to a brand can vary based on category and target, but anything that comes across as a surprise to its audience is a “problem.” The consequences can range from the general message being lost (because of shock) to decreased brand trust and all-around avoidance.

Overall, he said, an “opt-in approach” where consumers know what they are getting into before they actually get into it is the way to go.

However, Ann Cavoukian, executive director of the Privacy and Big Data Institute (PBDI) at Ryerson University and former information and privacy commissioner of Ontario said “opt-in” approaches aren’t always so black-and-white.

She pointed to the practice of serving ads through public wi-fi that most customers usually opt into — it’s doubtful users are reading through the entire set of terms and conditions, she said.

The terms and conditions page for retailer Urban Outfitters, which offers free wi-fi in its stores, is more than 1,400 words. The terms of use for Walmart’s free wi-fi access is more than 4,000 words. And the user agreement for the TTC’s in-station wi-fi, which extended this year to include all subway stations, is more than 2,200 words. According to BAI Canada, which partnered with the TTC to launch the network, use of the service is on the rise, with the company granting more than 2.5 million one hour sessions (on just over 300,000 unique devices) in February 2017 alone.

Most of the advertising bought on the TTC’s wi-fi platform is banner ads and is targeted mainly by time of day, but some advertisers can choose to do full takeovers of the system. That was the case for Twitter Canada, which for eight weeks in late 2015 granted users full-day access to the TTC wi-fi if they signed in through their Twitter accounts (they could bypass the option and be granted a one-hour session). The campaign was part of an effort to drive use of Twitter during commutes.

Kevin Callahan, head of business development at Twitter Canada, told MiC that the process saw about 60,000 unique sign-ins over the eight-week period (although the wi-fi option was not available at as many stations during the time) and that a large portion did sign into Twitter. However, he stated that the feedback received was quite neutral — and that the understanding of the exchange only seemed to rise toward the latter half of the campaign.

“At first people were definitely like, ‘What is this? How do we use this? Why do I have to sign into Twitter?'”

Cavoukian said the lack of understanding, even when users click the “I agree” button, shouldn’t come as a surprise given the way terms and conditions are laid out, and that it’s hard to say whether or not consumers are truly opting in from an informed stance.

“You can’t ask someone to read a lengthy terms of service and privacy policy that is full of legalese and jargon,” she said, and added that it’s reasonable to assume most people don’t actually read those policies.

She said brands should be proactive enough to offer a more concise summary of the terms and conditions stating in plain language what will happen, what kind of data is being used and what apps the advertiser will have access to.

“You have to make it real,” she said. “You have to make it accessible.”

She added that big data and privacy, ideally, should not be at war and can actually complement each other very well. She pointed to Air Miles, which the Privacy and Big Data Institute works with to use data from its loyalty program to help grocery stores create more personal targeted marketing. She said the company takes a clear opt-in approach, which creates a more informed consumer.

“There’s a misconception that privacy advocates are anti-marketing,” she said. “You can extract an enormous amount of value from big data, and all you have to do is address privacy-related issues upfront and proactively.”

Cavoukian agreed that compromising brand trust can drive away consumers, and added that the opposite is true. “Proactively offering privacy by design engenders consumer confidence and trust, leading to a competitive advantage.”

Assuming that privacy is not important to consumers would be a huge mistake, she said. “In the last year, three online surveys showed that the public’s concern for privacy has never been higher — in the 90th percentile — while their ability to control access to personal information has never been lower. So companies should get smart, listen to their customers.”

But with mobile ad targeting drawing comparisons to Minority Report for some, will the ever-evolving world of digital advertising win over skeptics? With OOH advertising now becoming increasingly integrated into mobile and digital advertising, the feeling of being “followed” can become all too real.

According to Abby Worthington, senior director, head of print and OOH investment with the DentsuAegis Network, digital does play a vital part in the evolution of OOH — and the choice to incorporate it isn’t arbitrary.

“We do not have scaled measurement of audiences against any given [out-of-home] location,” Worthington told MiC. “Up until now, we have relied on third party research such as Stats Canada, Environics and general market knowledge to provide insight into the type of audiences that would frequently be around a location.”

Use of more mobile data will allow advertisers to make better assumptions — and Worthington said feedback received by the agency shows that consumers are savvy enough to know how to opt in and out on their ad-serving mobile apps.

She also pointed out that Canadian privacy laws only allow advertisers to target by segment. The laws are fairly similar to other major markets including the U.S., although consumers have still called for more guidelines around targeting based on online activities in the U.S. and in the U.K.

But could targeting by segment still alienate audiences? Simon thinks there’s a possibility.

One of the biggest ironies, he said, is that mobile phones — often accused of distracting us and removing the personal touch from everyday life — is “about as personal and connected as you can humanly get.”

At least, when it comes to how much the devices know about you.

While connecting that data to OOH media is “fascinating” for Simon, he cautioned that it has potential to get “very controversial, very quickly” depending on what kind of data is incorporated into its targeting.

“If you’re essentially building a profile, that’s where I think the Minority Report feel is brought to the fore. People start to wonder, ‘How did it know that about me? How did it know that I was this age?”

As advertisers, said Simon, anything that can look like profiling or judging can be extremely risky.

“It crosses the line between serving for audiences and judging them,” he said. “Advertisers should be well-counselled and proceed with extreme caution.”

What looks like profiling and judging to Simon? Anything that makes assumptions based on income or possibly ethnicity is off-limits to him, but gender and age can be a safe go. “Knowing somehow if they are likely to have kids with them as well is also beneficial to prevent them serving an ad that is inappropriate.”

He and others brought up the example of Target, which famously figured out that a teenage girl was pregnant in 2011.

Overall, Simon, who admits to being “more risk averse” said he will probably always err on the side of caution. “The risk of negative backlash largely outweighs the benefits of increased targeting.”

Worthington said the more effective ways to tailor advertising through out-of-home technology involve incorporating the environment around the consumers — such as weather, day-parting, market and social triggers. Recent examples of brands incorporating the day-to-day world in advertising include alcohol manufacturer Pernod Ricard, which customized social and digital ads to complement the recent winter storm Stella on the U.S. East Coast, and U.K. Retailer Sainsbury’s, which matched its out-of-home clothing advertisements to real-time weather conditions.

It’s all about relevance, said Worthington, and relevance can be achieved without alienating consumers. But she did have one piece of advice for advertisers: “With everything advancing so quickly, avoid being status quo. Advertisers [should still] take advantage of these capabilities.”