London is due to get even more tech crammed into its every growing fleet of more futuristic buses, with top-deck seat indicators arriving on more services.

TFL has announced that the top-deck seat availability gadgets tested on two buses since last August will now roll out to an entire line. Passengers on the 59 between Kings Cross St Pancras and Streatham Hill will now be able to try out the service.

So how does it work? Using information from the CCTV cameras already on the bus a company called Timespace has developed a system that can recognise if a seat is in use. That way passengers boarding on the bottom deck can see on a readout just how many seats are free before making the rickety climb up the bus steps.

The aim of the technology is to make full use of bus space which might go unused at the moment as people don't want to gamble the climb to the top deck. Knowing there's a seat waiting should help get more people upstairs. Route 59 was chosen because of its overcrowding issues that this tech should help to solve.

Whether the other tech from the tester buses of last year, like Wi-Fi and more detailed screen read-outs, will reach more buses soon isn't clear.

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