Have you ever pressed one of those smiley face buttons in airports? In turn they translate your mood as: dark green - “Delighted”, green - “Happy”, pink - “Sad” and red - “Don’t even ask”. Well they don’t do anything. They’re placebos. Behavioural tools planted at strategic points in airports so the man can control your emotions and make you feel like you’ve been listened to. Or at least, that’s what I’ve been telling people for the past six years, since a supposedly reliable source tipped me off after the buttons appeared at Heathrow ahead of the London Olympics.

But last month I had an epiphany at Luton Airport. It was 2am, three hours later than my flight was scheduled to land. When I finally got through passport control I punched the red emoji in the face, twice, before turning to my girlfriend (said reliable source) and asking: “Are we sure these don’t actually do anything?”

It turns out, they do. They produce insights into when, and where, people are happiest and angriest across 160 airports in 36 countries, allowing staff to respond to negative responses in real time. After apologising for my ongoing smear campaign, I asked Heikki Vaananen, the CEO of HappyOrNot, how his simple idea has revolutionised the way airports work - one smiley face at a time.

Why does the world need smiley feedback buttons?

“We had the idea for HappyOrNot 15 years ago, when I was frustrated by the poor customer service in a local gaming shop in Finland. There was no way for me to voice my dissatisfaction, so I could not expect the business to ever improve.

“Our technology lets the relationship between consumers and businesses evolve. Customers feel more valued, and companies can refine and perfect their services.”

Are the results always logged?

“Absolutely. The results are logged and transferred via secure network to our web-based reporting service, where the results are amalgamated into the various charts and graphs, ready-made for analysis. There’s no doubt that the use of our terminals has two values; providing airports with extensive and useful data while also making travellers feel empowered and valued.”

When are the happiest times to travel?

“Looking at the data across all 160 airports we work with, the small hours at the weekend are the worst time to travel, while mornings midweek are consistently the happiest times.”

“Specifically, 9am and 8am are the happiest times to travel, and 2am and 3am the unhappiest (perhaps unsurprisingly). Tuesdays, Wednesdays, and Thursdays are the most pleasant days to travel; Sunday and Saturday the least.”

Which part of an airport is the happiest?

“In terms of areas within airports, security is the happiest part of the airport experience, while baggage reclaim is the most aggravating.”

What happens when someone taps a button multiple times?

“There are plenty of checks in place to make sure the data isn’t faulty and that children (or adults) don’t abuse the system. For example, if someone pushes a button lots of times in quick succession, our system picks that up and makes a note in the data.”

Which is the happiest airport in the world?

“Across the airports we work with in 36 different countries, Exeter Airport has the happiest data. This could be down to a number of factors, including both how they use our technology and how great their service is.”

How can airports respond to feedback in real time?

“One of the main functions of the data is real-time alerts. For example, if an airport bathroom is unclean, customers will likely press a ‘very unhappy’ button. If this happens a few times, management teams are alerted. The airport is then able to investigate and fix the issue, which will then be visible in positive results.”

Also read: Dan Buettner knows the secrets of happiness

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Does the red button get damaged more often?

“No. The terminals are incredibly robust, but we’ve not noticed red buttons taking more damage than any of the others. In fact, our buttons are tested by one million presses with 220N (318 psi) force. A short-range punch from a karate black belt averages 178 psi.”

The Telegraph Group London 2018 LTD