The app lets users know when they have entered the London Congestion Charge zone, and gives them the option to pay the charges through TFL, so that they can avoid fines.

It has now been updated to also warn drivers of proximity to other congestion zones, such as the London Low Emission Zone, Milan ZTL Ecopass Zone, Malta CVA Congestion Charging Zone and the Stockholm Congestion Charge.

The app, which is now available for the iPhone 6, also boasts additional features designed to help drivers. It now lets users see when they entered or exited the congestion zone, and when they paid. And the app now allows users to add other drivers, so that they can monitor multiple cars simultaneously.

Richard Harris, director of AutoAlert, said: ‘For many Londoners, knowing when and where to pay the congestion charge is a struggle. We work with a lot of companies that have fleets of vehicles, so we designed this app to make their lives easier.” ‘Our customers have already saved millions of pounds in congestion charge fines by using the app. This next update makes checking whether you are in the congestion zone even easier.’