Asimh

eSIM: What is it, and how does it work?

An eSIM is a digital SIM that’s built into most modern phones. It works like a physical SIM card, but without having to insert anything into your device. eSIMs offer tons of benefits, such as helping you avoid roaming fees and making it easy to switch between providers.

What is an eSIM?

An eSIM is an embedded subscriber identity module — essentially, a built-in chip in your phone. It does everything a traditional SIM would do, but without having to slot a tiny card into your phone. Additionally, an eSIM allows you to use several carriers and phone numbers at once, which is super convenient.

eSIMs are available on smartphones, tablets, smartwatches, and even some cars! They’re great for quickly switching between phone numbers and grabbing mobile data for travel.

How does an eSIM work?

An eSIM uses preinstalled software on your device to work just like a physical SIM. Once you activate it, you can connect to a cell network, make calls, and use mobile data. Most modern phones will have built-in eSIMs, but check our list of eSIM-compatible phones to see if yours does.

To start using an eSIM, just buy an eSIM plan and complete a quick setup. No need to remove your current SIM card — it can stay where it is, whether you decide to keep using it or not.

How to set up an eSIM

Follow these steps to start using an eSIM on your iPhone or Android.

Set up an eSIM on your iPhone with the Asimh app

Pick an eSIM data plan for your trip

Select the country you’re heading to and choose a plan.

Download the Asimh eSIM app

Get the app, tap “Install eSIM,” and follow the steps on the screen.

Your plan will automatically activate

Get ready for your trip — your plan will activate when you arrive.

Set up an eSIM manually on your iPhone

1. Go to “Settings”.

2. Tap “Cellular data” or “Mobile data”.

3. Tap “Add cellular plan”.

4. Touch “Enter information manually” at the bottom of your iPhone screen.

5. Paste the eSIM information shared by your provider.

Set up an eSIM on your Android with the Saily app

Pick an eSIM data plan for your trip

Select the country you’re heading to and choose a plan.

Download the Asimh eSIM app

Get the app, tap “Install eSIM,” and follow the steps on the screen to set it up.

Your plan will automatically activate

Get ready for your trip — your plan will activate when you arrive.

Set up an eSIM manually on your Android

1. Go to “Settings”, then “Connections”.

2. Tap “SIM manager”.

3. Select “Add eSIM”.

4. Tap “Scan the QR code” or choose another way to add your eSIM.

Set up an eSIM using a QR code

Scan the QR code to download Asimh

Use your phone to scan the QR and download the Asimh app

Buy an eSIM data plan for your trip

Get a mobile data plan for the country you’ll be visiting.

Your plan will automatically activate

Get online the moment you arrive at your destination.

eSIM advantages

eSIMs are the future of connectivity. Here are the main eSIM benefits.

No high roaming fees

Travelers can buy eSIMs that connect them to local carriers and avoid unexpected roaming fees.

Multiple profiles

You can have multiple virtual eSIMs on one device, making it easy to switch between different carriers and phone numbers.

Pay for what you need

Off to Japan for a week? Get a 7-day plan instead of monthly, and save your yen for an extra okonomiyaki.

Saves space

The absence of a physical SIM card slot frees up space for other device upgrades (like a bigger battery or more handset features).

Can’t get lost or stolen

Swapping out tiny SIM cards is tricky, especially if you’re on the move. An eSIM is built in, so it won’t get lost or stolen.

Less waste

A single plastic SIM won’t destroy the planet, but getting a newly packaged SIM card for every trip adds up over time. Use an eSIM instead.

eSIM disadvantages

Just like everything else, eSIMs have some drawbacks.

Not all devices support eSIMs. While most modern phones are eSIM compatible, if you’re using an older model, you may be out of luck.
Unfamiliar technology. If you’re new to eSIMs, you might find the activation process a bit more complex than simply inserting a SIM card.
Not easy to switch devices. Moving your eSIM to a different device involves more steps than just swapping a physical SIM card.

What is the difference between an eSIM and a physical SIM?

The main difference between an eSIM and a traditional SIM card is that an eSIM is digital while a SIM card is a physical chip.

	eSIM	SIM
Phone numbers	Up to two*	Up to two
Network Operators	As many as you like	Up to two
Removal	Deactivate the profile	Remove the SIM card
Activation	Manual or automatic (plan activates at your destination)	Manual (need to insert a card into your device)
Compatibility	Newer devices only	Old and most new devices
Using abroad	Affordable — easy to get data plans for different countries	May be expensive due to roaming

Frequently asked questions about eSIMs

What does an eSIM card do?

An eSIM is a digital version of a physical SIM card. It connects you to a mobile network, allowing you to make calls, send texts, and use mobile data. Instead of having to insert it into your device, you just need to buy an eSIM plan from a provider and activate it.

How can I get an eSIM?

You can get an eSIM from any reputable eSIM provider, typically by making an online purchase. For example, Asimh offers eSIMs in over 190 destinations — just find the country you want to use your data in and pick a plan.

Is eSIM better than a SIM card?

In short — yes. eSIMs are built into your phone, so you no longer need to open it up to insert a tiny card. These virtual cards are great for switching between providers and for international travel. Without a SIM card slot, phones can be made smaller or have improved features (like a larger battery). Here’s a more detailed comparison of an eSIM vs. a physical SIM.

Why would I want an eSIM?

You may want to get an eSIM for many reasons, like going abroad or needing extra mobile data to use in your home country. For example, if you’re heading to a country where you can’t get free roaming, buying an eSIM data plan can be an easy solution that won’t break the bank. Asimh offers plans from 1GB to 20GB (with unlimited plans coming soon!), so you can buy as little or as much data as you need.

Alternatively, you may want to get an eSIM because you’ve seen a great eSIM offer and want to take advantage of it. You don’t need to be going abroad to use it — eSIMs provide an excellent affordable mobile data option wherever you are.

Why are eSIMs not popular?

eSIM technology is still quite new — the first eSIM-compatible smartphone was only released in 2016. Not many people know about eSIMs yet, and those who do typically use them with wearable and IoT devices only. That said, their popularity is growing as more people find out about eSIM benefits. We think they’ll become a lot more popular soon.

Is an eSIM safer than a SIM?

Yes, in some ways. A physical SIM card can be damaged, lost, or stolen — especially if you’re swapping out cards on your travels. eSIMs are electronic and built into your device, so you can’t damage or lose them. They can’t be stolen either (unless you’re really unlucky and someone steals your device).

Does an eSIM work without an internet connection?

Yes, an eSIM can work without an internet connection. For example, with some eSIMs, you may be able to make cellular (voice) calls or send texts (SMS). What you can do with your eSIM depends on your eSIM plan and the provider you choose.

It’s worth pointing out that right now, the eSIMs you can buy from Asimh don’t give you a phone number or let you make voice calls without an internet connection. Instead, they give you data to connect to the internet, allowing you to make calls, send messages, and browse the web through communication apps.

Does an eSIM drain your phone battery?

Battery drain is not an issue with eSIMs, at least not more than with physical SIM cards. If your device has been using more battery power lately, it’s likely caused by other apps on your phone.

Can you convert an eSIM back to a physical SIM?

Yes, you can convert an eSIM back to a physical SIM — for example, if you want to use it with an older phone model. However, it’s best to pop into your network provider’s store to speak to an advisor and pick up a new SIM card.

Get an eSIM data plan

Find a mobile data plan for your next trip — search our list of destinations.