Travelling overseas is exciting, but staying connected can make a huge difference to how smooth and stress free the experience is. Reliable mobile data helps with navigation, transport, bookings, translation, and safety, especially in busy cities or unfamiliar places. It also makes it easy to stay in touch with family back home, which is something I value more and more as my kids start travelling independently.
In late November, my son Maddox and his girlfriend headed off to Japan for a two-and-a-half-week trip. Before they left, Holafly sent me two Japan eSIMs to test out so I could write about the experience for the Trail Hiking Australia community. If you want to test them out, they’ve provided a code for my followers too. Use TRAILHIKING at checkout to get a special discount.
I’ve used eSIMs myself in Switzerland and Peru over the past couple of years, but I’d never tried Holafly internationally, so I was keen to see how it stacked up as an option for Aussie travellers.
They were in Japan from late November to early December, bouncing between Tokyo’s busy streets, a few quieter suburbs, a couple of gardens and shrines, the interactive art museum, Disneyland, and Hakone near Mt Fuji. Perfect conditions for testing a travel eSIM: lots of moving around, lots of online navigation, and lots of chances for things to go wrong if you don’t have reliable data.
What pleased me is just how smoothly the Holafly eSIM worked for them. No data limits, no SIM swapping at airports, no fiddling around with local telco counters. Just install, land, connect, and go.
But before getting into the review, let’s break down what an eSIM actually is and how to set one up. If you’ve only ever used a traditional physical SIM card, this might be new ground.
What is an eSIM and how does it work?
An eSIM is basically a digital version of the SIM card you already use in your phone. Instead of popping in a little plastic card, the SIM lives inside your device and you activate it by scanning a QR code or entering a code from your provider.
Once it’s installed, it works just like a normal SIM: it connects you to a mobile network so you can use data, message friends, and run all the apps you rely on while travelling.
A few key things to know:
- No physical card: Nothing to insert or remove. Everything happens digitally.
- Easy to switch between plans: Most eSIM-enabled phones let you store multiple SIM profiles, so you can keep your Australian number active for calls and texts while using a travel eSIM for data overseas.
- Great for international travel: You can buy a plan online before you leave, install it at home, and have it ready to go the moment your plane touches down.
- Simple activation: Scan a QR code, follow a few prompts, and the profile installs itself.
- Works on most modern phones: iPhones, newer Samsung and Google phones, and many tablets and smartwatches support eSIMs. It’s always worth checking your device’s compatibility beforehand.
How to install a Holafly eSIM
Holafly’s installation process was straightforward. After purchase, they email you instructions plus a QR code for activation. You can install the eSIM before you leave Australia, which I recommend, but it won’t activate until you arrive in your destination country.
Here’s the basic setup flow:
- Open the QR code on another device (computer, tablet, or a friend’s phone).
- On your phone, go to Settings > Mobile Data > Add Data Plan.
- Scan the QR code or enter the code manually.
- Name the eSIM so you can tell it apart from your normal SIM.
- Once you land overseas, turn on Data Roaming for the Holafly eSIM.
- Your phone will automatically switch to the local partner network.
One important point: each QR code can only be scanned once, so make sure you do it on the phone you intend to use overseas.
If you use a dual-SIM or eSIM-only device, you can keep your Aussie number active for calls and SMS, just make sure your data is set to the Holafly eSIM so you don’t accidentally incur roaming charges.
Using the Holafly eSIM in Japan
My son and his girlfriend installed their eSIMs before leaving Australia but didn’t activate it until they landed in Tokyo. You do need Wi-Fi for installation, but thankfully Japanese airports have free Wi-Fi everywhere. If you’re not sure whether your destination airport does, it’s worth installing before you fly out.
Installation: “super easy” in his words
Because they were travelling together, they just opened each other’s QR codes on their phones and scanned them. The eSIM installed automatically and within a couple of minutes they were ready to go. No stress, no swapping SIM trays on the floor of an airport, no hunting for a local phone counter.
Coverage and speed
They travelled all over the place:
- central Tokyo
- a range of suburban areas
- gardens and shrines
- teamLab Borderless interactive museum
- multiple train lines
- Disneyland
- Hakone and the Mt Fuji region
Holafly advertises 4G and 5G coverage in Japan, and that lined up with his experience. Coverage was excellent almost everywhere they went and connection speeds were consistently fast. There were no dropouts and no issues loading maps, booking tickets, using message apps, or browsing online while moving around. The only times they noticed a slight slowdown were in mountainous areas and occasionally while travelling on the Tokyo Metro underground, which is fairly typical for any mobile network. Even then, connectivity remained usable and never became a problem.
Unlimited data was the real bonus
For context, my own Australian mobile provider charges $30 for 3GB on a 15-day international roaming pack. That’s tiny in 2025 terms, especially if you’re using maps, sharing photos, or jumping on video calls. The last time I relied on one of these packs overseas, the 3GB vanished in a couple of days and I ended up buying several more just to get through the trip. That was the moment I realised there had to be a better option, and it’s what pushed me toward using eSIMs instead of my standard telco’s roaming.
Holafly’s Japan eSIM costs around $118AUD (at the time of writing) for a 30-day plan with unlimited data. Plans start at 5.90AUD.
Yes, it’s more expensive than a basic roaming pack, but the difference is huge:
- no worrying about data limits
- no checking your usage every day
- no risk of being stuck without data in a foreign country
For travellers who rely heavily on Google Maps, WhatsApp, Google Translate, booking apps, and social media, unlimited data removes a lot of stress. It also makes navigation in dense cities like Tokyo far easier.
Staying connected to family (and me)
When they landed in Japan, the first thing my son did was message me to let me know they’d arrived safely. That alone makes the eSIM worthwhile. Throughout the trip they used unlimited data constantly, and I was able to use Find My Friend (on iPhone) to check in and see where they were. Not to pry, but because I genuinely enjoyed following their journey. I’d see their location pop up, then jump on Google to look up whatever area they were exploring at the time.
- sending photos
- booking transport
- checking train times
- finding restaurants
- navigating through Tokyo’s seemingly endless streets
- translating signs and menus
- messaging family and friends
- booking Disneyland tickets
- researching day trips and activities
He said he never once thought about how much data he had left, which is exactly the point of unlimited plans.
Any downsides?
There are a couple of things worth noting:
- Holafly eSIMs are data only, so you can’t make regular phone calls or send SMS. For most travellers, apps like WhatsApp, Messenger, or iMessage cover everything you need, but it’s worth keeping in mind.
- Holafly is not the cheapest eSIM provider on the market. But if you want unlimited data with reliable coverage, it’s one of the strongest options available.
As someone who has dealt with small roaming packs and patchy local SIM cards in the past, the convenience alone makes Holafly appealing.
Would I recommend Holafly?
Based on my son’s experience in Japan and my own previous use of eSIMs in other countries, I feel confident recommending Holafly as a solid, reliable option for international travel. Before becoming an affiliate, I was given a two-week Holafly eSIM to trial. I wasn’t travelling overseas at the time, so I couldn’t test it internationally, but I did switch off my regular telco’s data for the full two weeks to see how the service handled day-to-day use. It worked exactly as expected and gave me the reassurance I needed that Holafly was a dependable option before recommending it to others.
Their strengths are clear:
- Unlimited data
- Fast and stable coverage
- Easy installation
- Instant delivery and activation
- No roaming fees
If you’re travelling to Japan, or anywhere outside of Australia, and you rely on your phone for navigation, bookings, communication, and general travel logistics, Holafly takes a lot of worry out of the equation. It’s not the cheapest solution, but it’s absolutely one of the easiest.
Holafly does note that coverage is strongest in urban areas, and that in deserts, mountains, or dense wilderness the connection may be weaker or less stable. That’s true of most providers, and it’s something hikers and outdoor travellers are usually familiar with. In cities and towns, though, the connection has been excellent in our experience.
For hikers, walkers, and anyone exploring cities or remote areas where staying connected matters, the convenience is worth the price. And if you’re in the middle of planning an overseas trek, you might also find my article on essential travel tools helpful — you can read it here.
If you’d like to try Holafly for your next trip, here’s my affiliate link or use my code TRAILHIKING for a discount.
And if you have any questions about using an eSIM overseas, feel free to get in touch. I’m always happy to help fellow hikers and travellers make their trips smoother, safer, and a bit more stress free. If you’re in the middle of planning a bigger trip, you might also find my guide to Essential Travel Tools for Overseas Hiking Adventures useful. It covers the other services and apps we rely on when trekking overseas.
