I waved a rectangle of black-and-white squares in the vicinity of an optical scanner. The tiny computer's eye caught a fleeting glimpse of the barcode, de-skewed, rotated, and deciphered it - then checked its contents against a database. After a few milliseconds of deep thought, it opened the gates for me.

I handed over my passport to the border guard. They verified the cryptographic signature embedded in a chip, nestled deep within the document. Seeing it was valid, they waved me through the border.

I jumped on a train which sped 160 km/h underneath the sea! Although there's no WiFi 45m under the seabed, the rest of the time my various devices happily slurped up the bits from the æther.

I emerged blinking into a new city. My phone immediately latched on to a dozen satellites 20,000Km above my head. Within a few seconds it had pinpointed me to within 10 metres. I knew where I was. I received a text on my phone - my wife had tracked my journey and knew I'd arrived safe and sound.

My phone complies with all modern standards and frequencies; it spotted a 4G signal straight away. My SIM card did the usual authentication and negotiation dance with the local networks and they quickly granted me access. I have an IP address, therefore I am.

An army of volunteers had already mapped the city - down to the last restaurant, bench, and fire-hydrant. I knew where I wanted to go, but not the quickest way. Luckily, several decades of route-finding algorithm research kicked in and presented me with walking options.

The city's public transport timetables were all in a standardised format, so I was also able to see which bus and trams I could catch. The live display showed me the next bus was snagged in traffic a couple of streets away and wouldn't arrive for a while.

It was late, and I didn't fancy walking through an unfamiliar city. I know my locked phone is useless to a thief - unless they force me to unlock it - and can easily be tracked if stolen. But I could do without the inconvenience. So I opened up my taxi app - the same one I use at home - and a car arrived within a few minutes to take me to my hotel.

While waiting, I noticed a warning sign affixed to a lamppost. I don't speak the language, sadly. But I held my phone's camera up to it, and an instant translation appeared. It warned me that pickpockets operated in that area so I should keep my valuables hidden. I quickly put my phone in my pocket.

The conversation with the taxi driver was a little stilted. English was his 4th language, and none of the other 3 were ones I was conversant in. But voice-to-text-to-foreign-language worked well enough on the phone to have a pleasant conversation.

I'd like to say checking-in to the hotel was a magical experience where they recognised my iris prints and whisked me off to my room. But hotels are so 20th century! At least they gave me an RFID token to unlock my door - no magnetic strips to gradually demagnetise in my pockets, and no jagged bits of metal to scratch my screens.

I wandered down to a local restaurant. A happy community of vegans had already marked the best dining spots on a map and had left thoughtful reviews. I picked the one which had the opening hours updated recently.

Steered to a seat, I once again whipped out my phone and scanned the QR code on the table. It took me to a mobile website. There wasn't quite enough phone signal in the restaurant, so I hooked into their free Wi-Fi. A quick scan of their network showed they had proper client isolation, so I was lazy and didn't bother activating my VPN.

I tapped away on the menu - noting which standard allergens were present in each dish - and the food arrived quickly. Lovely! It was at this point my phone also started to complain about being hungry. Nestled next to my seat was the now-ubiquitous USB port. I slammed in a power-only USB cable (I doubt there was anything malicious behind the power socket - but computers are tiny and devious) and fed my helpful companion.

The bill came - as it always does - and I held a sliver of plastic next to the payment terminal. The funds were transferred instantly and with no transaction fees. Take that cryptocurrency!

On the way back to the hotel, I spotted ⚕️ - the Rod of Asclepius. I popped in to the pharmacy and picked something up to treat a minor complaint. The drugs were from a brand I recognised & trusted. Yes, I know it's lovely that each country has its own name for the same chocolate bar - but sometimes it is handy to have a standard name and logo which are easily recognised by those in a hurry.

A quick videocall with my wife as I walked down the street - two different phones, one encrypted app.

I finished the evening by hooking an HDMI cable between my laptop and the hotel room's TV so I could watch a movie streamed from my home server. Despite being in HD, a modern codec had squeezed it into a minimal file size. And, despite being in a strange country, my cable fitted perfectly.

Obviously, I stuck all my gadgets on charge before falling asleep. The laptop, headphones, and phone all take USB-C, so I didn't have to faff with lots of different charging bricks.

I gratefully fell into bed. My phone had already detected the time-zone change and knew to wake me at 07:30 local time.

The next morning, as I entered the office where I'd be working, I flashed yet another QR code at the entrance. Someone scanned it with their phone and verified that I was vaccinated against you-know-what.

And thus the week continued.

Was everything perfect? No. But that was rarely the technology's fault. It worked near flawlessly.

I remember having to hold huge paper maps to navigate around a city. Flimsy travellers' cheques for payment. Never knowing if the thing you wanted to see was open that day. Needing a different SIM - and sometimes a specific phone - if you dared leave your country's airwaves. Tiny phrasebooks with outdated slang and dubious translations. Pumping coins into a call-box to let people know you'd landed safely. Turning up to a transport hub only to find things were cancelled. Menus in incomprehensible languages. A scribbled bit of paper stapled in a passport as a vaccine certificate. A dozen different cables and adaptors for power and video.

Don't let anyone misguide you with rose-tinted nostalgia - the old world was rubbish!

I know at its heart, this has been a story about privilege. I went to a modern city with excellent tax-subsidised infrastructure. I have credit cards and I can afford a passport. My phone is new enough to do all the things I want. And I'm rarely troubled by cat-callers or other harassers when walking around a strange city.

But the future is now. I can seamlessly use my personal tech in a different country. I can navigate, pay, live, and survive. All mediated by tiny silicon wafers, high-frequency radio waves, and humble barcodes. The present is magical.