Open flight tracking app Plane Finder and time will disappear. Watching little yellow aeroplanes moving around a map and tapping to find out where each is going is utterly absorbing.

“We thought it was just going to be the nerds like us who loved the app, but there is so much more appeal,” says Lee Armstrong, co-founder and CTO at Pinkfroot, the developer behind Plane Finder.

“It was not really until the app was released and we were getting messages from taxi drivers, pilots and cabin crew using the app, that we realised the market was bigger.”

Plane Finder tracks the aircraft overhead, anywhere in the world, in real time. Tap on any plane on the map to find out what aircraft you’re looking at and where it’s going.

The app shows you an aircraft’s operator, flight path, landing time, altitude, speed and more. Tap the camera icon then point your device up at the sky and, through the magic of augmented reality (AR), the app will show you details about the planes overhead, pasted on the skyline. Go into 3D view mode and you can examine aircraft up-close.

Prior to Plane Finder, Armstrong, his now wife Jodie Armstrong and friend Mark Daniels were working for an IT technology firm. “We always wanted to do something outside of the daily grind,” says Armstrong. “It wasn’t until iPhone OS 3 came out in 2009 and MapKit was there we realised we could do something we thought was interesting,” he says.

The trio co-founded Plane Finder and launched the app in September 2009. “It started out as a hobby,” says Armstrong. “We had one off-the-shelf receiver that was in my loft. So we had coverage of the south of the UK,” he explains.

“But we were getting app downloads from everywhere. People in Norway, for example, were saying, ‘I want to see the planes near me.’”

The solution was to make their own receivers and send them out to a dedicated community of app users around the globe who wanted to help expand the network.

“Largely they’re in people’s lofts or on people’s roofs,” says Armstrong. “We’ve managed to instil this community spirit by responding to people and engaging with them… What amazes me is some of the far-flung locations that our receivers are in – in the middle of a jungle or on a shack.”

The company now has between 5,000 and 6,000 receivers everywhere from the Azores to Angola to Alaska.

This has allowed Plane Finder to have better flight-tracking data than the airlines themselves. “We sell the data to the airlines so that they can track their own aircraft,” says Armstrong. “Air traffic control areas are very segregated so to get that information airlines would have to contact all of them. We bypass that by putting the receivers out everywhere.

“In the early days we would get emails from pilots saying, ‘We’re using your app because our company can’t tell us what we need to know.’”

Some of the app’s most valued users are those with Autistic Spectrum Disorders (ASD), many of whom are passionate about plane spotting.

“ are very good testers who will help you shape the product. They will tell you immediately if something is not right – if you have the wrong photo or data. It increases the quality and pushes us to keep the bar high.” The company recently spent the day at London’s Heathrow Airport meeting the app’s plane spotting community.

Armstrong’s own passion for planes stems from his father, who was a helicopter pilot in the Royal Navy. “Ships, planes and aviation are in our blood,” he says.

“Because of my background, in the early days I made a decision to block all military stuff,” explains Armstrong. “Then in 2017 said, ‘Why are you blocking us? If we want something hidden, we will hide it.’” The Queen’s helicopter, for example, is not visible.

Today the company has relationships with the Ministry of Defence, the Civil Aviation Authority and NATO. “I have a really surreal memory of standing in a NATO meeting with all these member states educating them about our technology,” says Armstrong.

Unsurprisingly, Armstrong’s father also enjoys Plane Finder. “My father moves in circles with old friends and they will say, ‘Look at this app, Plane Finder.’ That’s a nice proud moment for him. And I love it when that happens to me, too.”