A trial just being started in Britain could mean the end of paper train tickets. Instead passengers would use smart charging by way of phones. A twelve month trial between the two big cities of London and Birmingham will see travelers no longer buying the old paper tickets and maybe even no more ticket barriers at all.

Instead of tickets, systems at train stations would pick up Bluetooth signals from smartphones, even if the phone was in a passenger's bag or in their pocket. The system would detect the passenger at the start of their journey and then again at the end of their journey.

Then the traveller would automatically be charged the best price for their journey on an app on their smartphone. The app would be linked to a bank account and the correct and cheapest ticket price would be taken from their account.

The program could speed up travel, as passengers would not need to buy a paper ticket or top up pay-as-you-go cards before traveling. If the trial works, the new system could be rolled out across the UK to other train networks.

The rail industry has been slow to change from the old paper ticket system, which has been used for a very long time. More and more people are used to paying for things directly from their phones and this could be the next big step for rail ticketing as well.

The trial comes at a time when record numbers of people are taking rail travel in Britain, around 1.7 billion trips this year, which is twice as many as used rail in the mid-1990s.