Lunch hour has just started in the north London borough of Camden, which means it's crunch time for Billy Shannon, a fresh-faced food delivery courier.

Dressed in thermal clothing to ward off the autumnal cold, the 18-year-old jumps on his bike as an order comes in, mindful that he is paid not by the hour, but by the number of deliveries he makes.

"Yesterday, I was here for six hours and I only made six deliveries, so I only made �3.75 ($4.67, 4.40 euros) an hour," Shannon told AFP.

This is well below the minimum wage for his age of �5.55 an hour -- one of the reasons he has joined a legal challenge on Monday against his employer, Deliveroo, to win union recognition.

"We want to be recognised as workers, so we have rights such as the national minimum wage, the right to protection against discrimination, and paid holiday," Shannon said.

Most Deliveroo couriers around London are paid �7 per hour and an additional �1 per delivery, but those in Camden operate under a new pilot scheme that abolishes the hourly rate for a payment of �3.75 per delivery.

"I do not make money unless I make a delivery, so Deliveroo do not see me sitting in the rain, waiting with my app on in Camden, as work," Shannon said.

After the previous day's disappointments, today is looking better.

As the wind picks up and the clouds above start to darken, Shannon logs onto the Deliveroo app and turns on the "Available for orders" option.

He has barely logged on when an order comes through. Once he delivers that, a second swiftly follows, meaning that within an hour he has made �7.50.

Shannon took the job this summer after leaving school -- mainly because he likes cycling -- joining a growing band of 8,000 Deliveroo couriers across Britain.

Wearing the turquoise and grey company uniform and a box with its logo on his back, they are a distinctive group speeding their way through London's streets.

But Deliveroo does not recognise them as workers but as independent contractors, who are therefore not entitled to certain key employment rights.

If Shannon and other couriers from Camden win their case for union recognition, the company would be forced to change their status.

"I feel like I am being exploited by Deliveroo," Shannon said.

"In order for them to make money, all other costs are on me, all the risk is on me and the restaurant, none of the risk is on Deliveroo.

"They sit there making millions and millions of pounds... while I struggle to make the minimum wage on a delivery."