They kind of bootstrapped around this quite well. The first product was a better Google Maps app, which meant they got people's journey data. I wonder if the real problem they ran into was just that public transport in London is pretty excellent, so even with journey data plus the ton of data that TFL provide, it's pretty hard to actually run anything better.

> public transport in London is pretty excellent

Really ?!?

I'm pretty sure most Londoners would disagree with that. Dirty, expensive, crowded, strikes and signal failures. TFL doing everything possible to avoid telling the truth, stating "good service" when everyone on the platform can see they're having a bad day in the office (again !).

Compared to the Japan, the Nordic countries, Switzerland, South Korea, just to name a few, London is dire.

Look at Japan, specifically Tokyo. More populous and densely populated than London. Yes the trains can get a little crowded at rush hour. But I've been visited a good few times now and I've never experienced the London-style horrors. Everything is punctual, clean, no strikes or signal failures. And that's just the Tokyo subway. The Shinkanzen is simply fabulous. Its great !

When I used to write software like this. We typically had some sort of 'vpn', it was usually an isolated network 100% so you did not need that in the first place. For this I would have used an MDN on an isolated network. We would then write a solid bootstrap program with a watchdog on an ISR. Basically it would have an A/B area then we could flip between them as needed. If a particular version did not come up on a vehicle we could default it back to the old version. Usually some sort of flag that said 'yep this version is solid use it from now on'. Usually also the program itself could declare itself as bad usually catching itself in the crash and writing something out somewhere.

Not 100% as vehicle env is pretty harsh. +/-12V in 1-2 seconds on crank so you better have something to deal with that. -40f to +150f so you better have HW that can deal with that. Worry about how much flash wearing you have left. Oh and just general bouncing around, kicking hitting, coffee spills so your hardware better be decently hardened. Even then you still usually had those 10-20 vehicles that you just had to touch them. Usually it would be in the middle of Montana somewhere. If you were lucky it could be at a terminal. Oh and dont cost too much as your competitors probably have better and cheaper hardware.

You don’t want to get in the hardware business here and in most countries you are probably not even allowed to deploy your own raspberry-pi based solution in a public bus, because it doesn’t fulfill the necessary security requirements and certifications.

That is why you have specialized sub-contractors who provide you with tested, certified, ruggedized hardware which you can install into the vehicles. It will also have connections for most proprietary ports you find in those environments. Of course it’ll cost you.