There is more than one way to commit fraud and, for some rail travellers, it has been as simple as a couple of taps on their phone as their train approaches its destination.

That telltale last-minute purchase of a digital ticket – for the shortest journey that will allow them to bleep through the gates, regardless of how far they have travelled – is one of a number of illegal wheezes that train operators are trying to eliminate, with the enthusiastic backing of the government department that will directly oversee most of England’s rail services when they are renationalised next year.