THE SONET JOURNAL

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Notes on travel, data, and saying it well. Thirty short lessons on eSIMs, thirty destination guides, and the tools in between.

Vietnam by scooter and street stall

FEATURED · eSIM EDUCATION

What is an eSIM? A plain-language guide

No jargon. What an eSIM actually is, how it differs from a plastic SIM, and why travellers adopted it first. A plain guide before your next trip.

8 MIN READ · UPDATED FEB 2026

Tool · 2 MINUTES

eSIM compatibility checker

Check my phone →

ARTICLE · INSTALLATION

How to install an eSIM in two minutes

A step-by-step guide to installing an eSIM: what you need first, the actual install steps, and how to confirm it worked before you travel.

3 MIN READ · FEB 2026

Japan for the first time: a week that says it well

Japan · FROM €26.67

GUIDE · ASIA

Japan for the first time: a week that says it well

A first-timer's Japan itinerary built on restraint: three unhurried days in Tokyo, three in Kyoto, and a final day left open for Nara, Osaka or Kamakura.

12 MIN READSee Japan plans →

OFFER · SUMMER IN EUROPE

One plan, thirty countries, zero roaming sonnets of regret.

Regional Europe eSIM. Install once, hop borders freely.

Browse Europe plans10 GB · FROM £4.99

Latest lessons

eSIM education · 30 topics →

Nº 30 · CHECKLISTS

The travel-day checklist

6 MIN →

Nº 29 · INSTALLATION

After the trip: should you delete your eSIM?

4 MIN →

Nº 28 · DEVICES

eSIM for tablets and smartwatches

5 MIN →

Nº 27 · DEVICES

Unlocked vs carrier-locked phones

5 MIN →

Nº 26 · DEVICES

Battery myths, tested

5 MIN → All 30 lessons →

Tool

Will thy phone take an eSIM?

Two questions, a plain answer.

Check my phone

The postcard · monthly

One letter a month. No spam, only stanzas.

Guides by destination

30 destinations · All guides →

Vietnam

FROM €26.67

California, honestly, and only California

United States

FROM €26.67

Bergen to Oslo, the honest cost of the view

Norway

FROM €26.67

All guides

30 destinations →

The complete index

30 lessons · 30 destinations · 3 tools

I. The education syllabus

Nº 01What is an eSIM? A plain-language guide Nº 02eSIM vs physical SIM: what actually changes Nº 03Is your phone eSIM compatible? The full list Nº 04How to install an eSIM in two minutes Nº 05Activate before you fly: the pre-flight ritual Nº 06Data roaming explained (and why it costs so much)Nº 07How much data do you need for a week abroad?Nº 08Keep your number, carry our data Nº 09Dual SIM done right: home line plus travel data Nº 10What happens when your plan runs out Nº 11Topping up abroad without tears Nº 12eSIM on iPhone: step by step Nº 13eSIM on Android: step by step Nº 14QR code vs one-tap install Nº 15APN settings, demystified

Nº 16Why your eSIM shows "No service" (and how to fix it)Nº 17Hotspots and tethering on a travel eSIM Nº 18eSIM security: is it safer than plastic?Nº 19WhatsApp, iMessage and your eSIM Nº 20Country vs regional vs global plans Nº 21Two countries, one trip, one eSIM Nº 22eSIM on cruises and ferries Nº 23In-flight data: myths at 30,000 feet Nº 24Business travel: receipts, VAT and expenses Nº 25How eSIMs actually work: the tech behind the tap Nº 26Battery myths, tested Nº 27Unlocked vs carrier-locked phones Nº 28eSIM for tablets and smartwatches Nº 29After the trip: should you delete your eSIM?Nº 30The travel-day checklist

II. Thirty destinations

Australia€26.67 Brazil€26.67 Canada€26.67 China€25.07 Croatia€14.10 Egypt€11.40 France€24.90 Germany€26.67 Greece€6.83 Iceland€26.67 India€26.67 Indonesia€26.67

All 30, A to Z →

III. Tools

eSIM compatibility checker→

Data calculator

Coverage map