Anyone who has landed somewhere new and watched their phone fail to load anything knows the feeling. The maps app spins, the ride app spins, and you start eyeing the airport Wi-Fi sign as if it owes you money. What’s changed in the last couple of years is how much more of a trip now runs through that phone, and specifically through AI. The translator you were going to use with the taxi driver, the assistant that was going to explain the menu, the trip planner that holds half your bookings: most of it quietly assumes you have a connection.
So the old advice about buying data abroad matters more than it used to. It’s also part of why a growing number of people go for eSIM over physical SIM when they travel internationally. You can sort it out at home, land already online, and never queue at a SIM kiosk. Choosing a plan that suits your phone, your route and your AI habits takes a bit more thought.
The AI question nobody asks before buying data
Not every AI feature needs the internet, and that’s what decides how much data you’ll burn.
Google’s Live Translate, which handles spoken conversations in real time, depended on a data connection until recently. Google has since added an offline mode, but (and this is a big but) only on the Pixel 9, Pixel 10 and Pixel 11 for now, according to its own support page. Older Pixels, Samsung phones and most other Android handsets still need data for live conversation translation. Downloaded text translation is a different story and has worked offline for years.
Most of the rest sits in the cloud. That covers AI assistants you talk to, the ones you point your camera at, and most AI trip planners. AI glasses are in the same boat. They’re quickly turning into Big Tech’s next battleground, and the translate-what-I’m-looking-at features generally lean on the phone in your pocket for a connection.
The easiest way to find out what you’ll actually need is a little embarrassing in its simplicity. Put your phone in airplane mode at home and try every AI thing you’re planning to use on the trip. Whatever stops working is your data budget.
Coverage, and why Costa Rica is a good warning
Take Costa Rica as an example of how coverage can fool you. San José is well connected. A day or two later you might be driving a volcano road, or sleeping at an eco-lodge next to a national park, where the signal comes and goes. Those are precisely the places where a translator or directions would be most useful.
Travelers planning that kind of route often begin by comparing the best esim for Costa Rica options, so they have working data the moment they land. Roamify is one of the providers selling country plans there, without a contract or a physical SIM to swap. Once coverage checks out, the real differences between plans tend to be in the less exciting details: how many days the plan lasts, the data cap, the activation process, the refund policy, and how painful topping up is.
Coverage maps are fine as a rough guide, but I’d give more weight to recent reviews from people who went to the same corners of the country, not just the capital.
How much data AI really uses (honestly, it depends)
I’d love to give you a tidy figure, but there isn’t a trustworthy one. Typing questions to an assistant barely registers. Speaking to it uses more, and anything that streams video from your camera uses a good deal more than that.
A better approach is to measure your own habits. Pick a normal day at home and use your phone roughly as you would abroad: maps, messaging, a handful of translations, maybe a voice chat with an assistant. In the evening, check data use per app in your phone settings. Multiply by the number of travel days and add a generous margin, since getting lost tends to involve a lot of map refreshing.
People who expect to use voice translation or camera assistants every day should probably buy more than feels reasonable. Having a few gigabytes left over at the end is much less annoying than running dry on day four. If you’re working remotely, get the hotspot terms in writing too.
A few checks before you pay
The phone needs to support eSIM and be carrier-unlocked. It sounds obvious, yet a surprising number of setup problems come down to one of these two.
Install the eSIM before you leave, on home Wi-Fi that actually works. Trying it over a weak airport connection while your travel companions stare at you is not the way to start a holiday. A provider app that shows remaining data and days left is worth having, as is support that responds in hours rather than days. Privacy is worth a minute’s thought as well: a clear privacy policy, a protected account, and some way to switch the plan off remotely if the phone is lost or stolen.
Which kind of plan suits which kind of trip
Traveler | What matters most | What to watch for |
| Short trip | Simple country plan, quick setup | Data expiring before the flight home |
| Heavy AI user | Plenty of data and stated speeds | Plans that throttle after a few GB |
| Remote worker | Large allowance, hotspot permitted | Speed caps after heavy use |
| Family | Easy tracking across several phones | An account only one person can manage |
| Multi-country route | Regional coverage with named partner networks | Gaps at borders, on islands, on cruises |
Small print worth reading twice
“Unlimited” deserves suspicion. Plenty of unlimited plans slow to a crawl after a certain amount of use. That’s tolerable for messaging, but live voice translation tends to fall apart on a slow connection, often halfway through a sentence while someone waits for you to finish.
Hotspot rules, top-up steps and regional coverage lists are the other things to read properly. If topping up means creating a new account or emailing support, imagine doing it late at night in a station with very little battery left. And check whether a regional plan really includes every stop you’ve assumed it does, layovers included.
The market is not short of options. Grand View Research puts the global eSIM market size at $11.9 billion in 2025 and expects $17.7 billion by 2033. A detail that rarely gets mentioned: around two-thirds of that revenue comes from machine-to-machine uses such as connected cars, not from travelers. The travel segment still has more providers than most people have time to compare, which is exactly why comparing them carefully pays off.
Letting an AI choose for you
You can use an AI assistant to narrow down the field. Ask which plans cover your route and what trade-offs to consider, and it will usually give you a decent starting list.
I wouldn’t let it make the final decision. These systems can be misled, sometimes embarrassingly easily. One journalist managed to get ChatGPT and Gemini repeating claims from a single fake web page within about a day. Prices and coverage also change faster than any model keeps up with, so confirm the details on the provider’s own site before paying.
Stretching the data you buy
Offline maps and downloaded translation packs, set up before departure, will probably save more data than anything else here. Turning off automatic app updates, cloud photo backups and background refresh for apps you won’t use on the trip helps too. Video calls are better left for decent hotel Wi-Fi.
Banking is the exception. Mobile data on your own eSIM is generally a safer bet than café or hotel Wi-Fi for anything sensitive.
If your phone can store more than one eSIM profile, keeping a spare installed costs nothing. It means that when the main network fades in the mountains, switching takes a few seconds rather than a support chat.
A few common questions
Q. Will AI translation apps work without data?
Partly. Downloaded text translation works offline, and Live Translate does too on Pixel 9, 10 and 11 phones. Most voice and camera features still need a connection.
Q. Do I need to turn off data roaming?
For your home SIM, yes, unless you enjoy surprise bills. For the eSIM line itself, follow the provider’s instructions, since some travel plans need roaming switched on.
Q. Can I keep my regular number working?
Generally, yes. Many phones let the home SIM take calls and texts while the eSIM handles data.
Related: How AI Is Reshaping Travel in 2026: From Trip Planning to Touchdown
