A few months ago, we landed in a foreign country, opened the same Uber app as we used back home, and booked a cab. It just worked. I didn't need to register for a different version. I didn't need to create a new account. I didn't need to add a new credit card. That's the sort of seamless experience which can only come from a centralised service.

But, hey, we're all moving to a ReDeCentralised Federated Future. Nae king! Nae quin! Nae laird! Nae master! We willna' be fooled again! So let's think about how a decentralised Uber would work.

Broadcast

In the days before mobile phones, we could have used something like CB radio. Broadcast a message to everyone in a few miles saying you want to travel from point A to point B.

Cabbies, or their agents, could reply to you with their availability and prices.

But that puts a lot of work on you to manage all the replies. And you have no idea of the driver rating. And you'll be broadcasting your location to all and sundry.

And, sadly, modern handsets have no concept of a broadcasting in a P2P manner.

Perhaps a little centralisation?

In most parts of the world, taxis are regulated. You don't want rapists, thieves, and murderers driving you home late at night. You want a predictable fare calculated by an honest meter.

So let's say you have an app which knows your location, and send your request to the taxi-regulation-boards which cover your area. They can then broadcast out the request to all drivers, they confirm the fare, and then send it back to you.

I guess that could work. Think of all the taxi-regulators as little ActivityPub servers, and the cab drivers getting a stream of requests on their federated timeline. Your phone could receive "accepts" from multiple drivers and you could pick the one you like.

But how would your phone know which local taxi services are available? You would need a centralised list of them!

FOAF and Signed Claims

One of the supposed advantages of Uber is that it allows participants to rate each other. Passengers don't want to get in a car with an arsehole. Drivers don't want to pick up people who litter.

How would that work without a central entity? Could there be a solution with Verified Credentials? Have all participants write cryptographically signed ratings to a *spits* Blockchain?

Reputation Systems are hard.

User Needs

Of course, before sketching out such a system, it probably helps to sketch out some vague thoughts on what users actually want from a taxi system - and how decentralisation would help.

Firstly, who are the users?

As a driver, I don't want to have multiple phones and apps stuck to my dashboard.

As a user, I only want to use a reputable driver. But who determines reputation? What options do I have if something goes wrong?

Basically - what are the advantages of decentralisation in the taxi space? Users want competition on price and service - which they don't get if Uber are a monopoly. Users also don't want to deal with dangerous drivers - which is easier to enforce if there is only a single platform.

Drivers don't want their livelihood ruined by unjust reviews - how could that be enforced with a decentralised platform?

We haven't even got to payments yet!

Basically, it's not clear to me that is a compelling user need for decentralisation. Don't get me wrong, I like it as a concept. But I see it as exchanging one set of wicked problems for another.

Does this already exist?

Well, ish. There are various different attempts to build federated delivery services and the like.

But I am very interested in being proved wrong! Is there a decentralised takeaway service I should investigate? Are there federated hairdressers? Does anyone offer an open protocol for domestic cleaners?

I agree with Paul Carr when he describes Uber's crushing desire to "disrupt" as a fanatical form of hyper-libertarianism which could have decidedly nasty consequences.

However, I thought I'd try it out for myself after being given a £20 free voucher.

The app is lovely, and it had some delightful features - for example, I could take a photo of my credit card rather than manually typing in the numbers.

Emerging from a party by London's Westminster bridge I pulled out the app. It located me quickly, told me there were several cars in the area. I clicked a button and a few seconds later had a call from my driver to let me know where he was. It took us longer to cross the street to the pick-up point than it took for the car to arrive. Impressive!

The car was sleek, black, luxurious. The driver was friendly and we chatted about the Uber service. As we stepped out of the cab at our destination, my phone buzzed with the emailed receipt of the journey.

That's the other advantage to Uber, no need to deal with cash or a tip - everything is built in. No wallet, no problem - they money is seamlessly taken from your card.

That was the last impressive thing about Uber. Everything else is a bit shit.

For a start, the pricing is opaque. There's no meter in the cab, the app doesn't give any information, and the website is frustrating to use on a mobile phone.

The first indication I had of the price was when I received the bill via email. Youch! Fourteen quid for a couple of miles. I eventually found their pricing structure - it's essentially double that of a Black Taxi.

Still, it was free, right? Nope! Uber charged me £4. Why? I had a £20 voucher.

After reaching out to Uber via email (they don't seem to take phone calls) it turns out that when I signed up, they applied a £10 bonus to my account. Now, I don't know about you, but I expect £10 + £20 to equal £30.

Uber don't. The vouchers are separate. Rather than applying the largest voucher first, or anything useful like that, they treat them as distinct entities. So my £14 journey was reduced to £4. Leaving me with £20 to spend later.

Annoying, but not catastrophic.

Last night we decided to try using Uber again. Around 2230 on a Tuesday night, whipped out the app, it showed drivers in the area, with an estimated pick up time of 5 minutes. Click click click, cab booked.

Then this came through.

Seventeen minutes? I was in Bloomsbury - not the frozen wastelands of Balham! To be frank, a five minute wait saw a couple of black cabs drive past us. A 6 minute wait and there was a bus direct to our destination.

So I hit cancel and we jumped on the 188 back to Waterloo.

Who Is Uber For?

Uber isn't a bad concept. They've got a lovely app, and delightful cars. They attitude to customer service is very mixed - great drivers, poor back end staff.

One of the reasons that Silicon Valley is so "disruptive" is because San Francisco and the surrounding areas are <whispers>a little bit crap!</whispers> Public transport in the bay is patchy - and nowhere near as convenient as London. Their underground service didn't seem to connect with the train service, bus stations never seemed to be around when you needed them, cabs were dirty etc. In that environment, I can see Uber florishing.

But London - oh my darling London! - is different. You can't sneeze without hitting a Black Cab, the drivers are knowledgeable and the cabs are clean. For all its faults, the tube takes you to within spitting distance of most places. Buses, in the centre, are regular and full enough for me to always feel safe on them.

So, who is Uber for?

• People with more money than sense.
• The select few who are desperate to give the appearance that they have a luxury car service.
• Those who are currently ignored by taxis.
• If you've lost your Oyster card and wallet, but still have your phone.
• Anyone with severe class-phobia who still thinks Maggie was right about riding the bus.

If you really need a taxi and can't find one on the streets, consider using Hailo to hail a black cab. The price is cheaper, the service is quicker, and the drivers and vehicles are fully vetted and insured.

I still have £20 Uber credit, in the unlikely event that I find myself in Central London with no taxis, buses or tube stations - I think I'll just walk home.