Having two active phone numbers on the same device will likely appeal to some people. Photo / Luis Alvarez, Getty Images
Having two active phone numbers on the same device will likely appeal to some people. Photo / Luis Alvarez, Getty Images
ANALYSIS
Sometimes, small technological changes can have a much greater impact than is immediately obvious.
For mobile service providers, embedded subscriber identity modules, or eSims, are that kind of tech. eSims have been around since 2016 and are now available in newer smartphones and wearables like smartwatches.
Instead of thelittle plastic physical Sim registering your phone on a telco’s network, you download a software version instead and install it on a chip on your phone.
You can have lots of them on newer phones. Apple suggests eight or more eSims can be installed on the iPhone 14 models, and it’s easy to switch between them.
Then, you can have two active phone numbers on the same device, which will appeal to some people.
The remote provisioning of eSims is the key attraction.
What your phone screen might look like with an eSim, in this case capable of supporting both 2degrees and One NZ phone numbers.
Instantly available software eSims are replacing the plastic Sim cards with integrated circuits that you had to visit a telco store to obtain, or order and have sent to you.
Apple has already gone full eSim in North America, where iPhone 14s no longer have a slot for cards. This is big, and mobile telcos do not like it as it means they’ve lost their monopoly on that part of the sales conversation with customers.
What’s more, eSims can be bought and installed directly and easily from the Apple App Store and Google Play on your phone.
Google has the Fi service, with affordable eSim plans that come with add-ons YouTube Premium and storage, and they’re used to sell Android-based phones.
Fi is aimed at the North American markets, but you can see why mobile telcos are feeling queasy at the thought of eSims.
Pros and cons
The DIY cellular mobile network hook-up is possible due to another wireless technology: Wi-Fi, allowing you to obtain eSims anywhere in the world. It has to be stable Wi-Fi as you don’t want the installation to be interrupted.
One thing to watch out for is that many eSims can only be installed once. Delete the eSim, and you might have to get a new one.
Also, it’s not a matter of popping out a Sim card and inserting it into another phone for use on that device. As it’s not physical, an eSim has to be transferred wirelessly, with both devices powered on.
No physical cards means eSims can actually be more secure. Sim swapping to hijack your phone and its number should be more difficult with eSims. Criminals can’t call up a provider to pretend they’ve lost phones and order replacement physical eSims.
Add multi-factor authentication, and it really should be harder to break into the devices that we store heaps of personal and financial information on.
eSims can also be a way to avoid paying extortionate mobile roaming charges.
Criminals can’t call up a provider to pretend they’ve lost phones and order replacement physical eSims.
Getting a data Sim at your destination and using internet services over Wi-Fi is usually the recommended money-saver.
It’s inconvenient, however. Sleepily figuring out which Sim to buy at the local telco shop at the airport or in town is no fun. Show your passport, have staff fiddle with your phone and you might have to buy a pricey “tourist” Sim.
And, you lose access temporarily to your home phone number with a foreign Sim.
Now you can use the app store for the phone platform of your choice and get a data eSim for the country or region you’re travelling to before departure.
The idea is to put all data at the destination through the eSim. Don’t let data roam via your home Sim, or make calls or send texts on it, or roaming charges will kick in.
Travelling friends swear by this, and they get notifications of calls and texts, and those important two-factor authentication codes arrive, as your home number is active but not roaming.
If you try it out overseas, take great care to follow all instructions to the letter and be aware that not all telcos everywhere behave the same.
North American mobile customers pay for calls they receive.
On Apple iPhones, you should be able to use FaceTime and Messages to communicate with other iPhone users without roaming charges as the end-to-end-encrypted services use data first; cellular only kicks in if data is not available, but this can be tricky to control.
To be on the safe side, stick to one of the many third-party messaging and calling apps that are data-only.
The process is a little more geeky than I’d be comfortable recommending for general use, but get it right, and it does offer compelling advantages.
To see how it actually works, I got an Airalo eSim with a tiny one gigabyte of data for seven days on it. It cost NZ$7.59, and there’s another thing to think about: travel eSims are convenient, but the cost can add up and not be worth it for shorter trips.
Airalo connected to One NZ’s 4G network, and I had them and 2degrees running on the same iPhone, which did a good job of displaying that two Sims were active.
However, Airalo in New Zealand results in “tromboning” of data traffic.
Traffic tromboning adds delay (latency) as data travels over several networks in Europe and the United States on Airalo before returning to New Zealand.
The delay kills performance, as data bounces back and forth over long distances.
On Airalo, I saw latencies of over 500 milliseconds. Most internet data access still worked okay, but some web-based applications performed suboptimally.
When more people opt for greater choice via multiple eSims for travel and other scenarios, issues like data latency should get sorted out with traffic taking shorter and more direct routes.
When that happens, how far away are we from big global telcos - or device vendors themselves - stepping in and out-competing local mobile providers, considering the latter have already divested themselves of their cellular tower networks?
