Mobile Phone Use During International Travel

Times Change

On our first international trip since the COVID pandemic I found the options had changed for getting cell (mobile) phone service in a foreign country. On our end there were two big changes:

  • We switched to a cellphone plan that does not support roaming outside of North America.
  • We switched to iPhone 11 Pro phones that support an eSIM (electronic SIM) in addition to an older style physical SIM.

Data Only eSIMs For Travel

It is possible that there were providers of data only travel eSIMs in previous years but I was unaware of them prior to this trip. The one we picked is installed through an app that, in turn, you install from the iOS app store. You can purchase the eSIM you want through the app and pay for it via Apple Pay all very conveniently implemented, it only takes a few seconds to select, pay for, and install an eSIM.

There are a bunch of eSIM options based on:

  • Coverage for a specific country, coverage for countries in a region, or worldwide coverage.
  • Amount of data.
  • How long before the eSIM expires.

For our phones I picked a single country eSIM with 5 GB of data and 30 days of use from time of activation. We were able to install and configure the eSIM before leaving home and then activate it when arriving at the destination airport. The pricing seemed to be very competitive with purchasing a SIM at the destination and a lot more convenient.

A data only plan could be limited in its appeal but it turns out that on our iPhones the “WiFi calling” feature is really a “Internet Calling” feature. So our North American only voice, text and data SIM will do calls and texting over the data provided by the data only travel eSIM exactly the same is it would over a WiFi connection. Since our cellphone plan does have international calling, just not roaming, we were able to use our US cellphone number via data calling to call restaurants and hotels as needed to make reservations, etc. And calls to other people traveling with us were considered US domestic calls by our cellphone provider.

A number of people traveling with us had international roaming on their phones and it seemed that our country specific data only eSIM got better coverage than their phones. I am not sure how much of that was due to the differences in phone hardware versus how much was due to the roaming partners their plans used versus the carriers that our eSIM used. At the very least, I think our coverage was on par with and probably quite a bit better than those using international roaming on a US based cellphone plan.

The data only travel eSIM setup is very slick and I would probably use it even if our cellphone plan had international roaming as the cost of the data only eSIM was very low compared to the international roaming we had on our old cellphone plan.

Minor Issues

There were a couple of issues that we ran into however. The first one was well covered in the provider’s documentation and video tutorial: The configuration in the iPhone settings needs to be correct. Basically you want your US SIM to be primary for calls and texting but have data roaming turned off. And you want the eSIM to be setup for data only.

The other issues were not covered, at least not where I noticed them.

Power Consumption

The US SIM needs to be active for your phone calls and texting to work. But since it cannot connect to any cellphone tower it is always scanning for coverage and that eats up the battery. If I deactivated the US SIM then the power consuming scanning for a cell tower stopped but it also then stopped doing WiFi/Internet Calling. So the SIM had to be active.

Perhaps there is a way to put one SIM into “airplane mode” with the other not but I did not find it in the iPhone settings. It seemed we were either in airplane mode for both SIMs or both SIMs were looking for service.

We do a lot of hiking in areas where there is no cellphone coverage so we are used to setting the phone to airplane mode to save our batteries. With the travel eSIM setup that goes double as the phone really seems to use twice as much power looking for both sets of signals.

In a more urban environment, especially if you are able to top up your battery, this is not as much a problem. It is just something to be aware of.

No Out of Data Message

For most of our trip we had usable WiFi coverage in our hotels. Between being in airplane mode during hiking and WiFi when in the hotels we used very little data. But the last hotel we stayed at we could not get the WiFi to work at all. They had a funky setup with each room having its own WiFi SSID provided by a small powerline connected box located in the room. For our room, we could connect but could not get out to the Internet. And our per room SSID was not available in other parts of the facility.

Since it was near the end of the trip and we both had about 4 GB remaining of our purchased 5 GB eSIMs we thought we would not bother the owners of the small family owned hotel and simply use our mobile data. That worked for one phone but the other quickly ran through its remaining data. I am not sure why that phone used 4 GB of data in less than two days but will look into that later.

But the “out of data” symptoms were not what I expected. I guess I expected an alert presented through the phone’s normal notification system. That did not happen.

There were some apps that said they could not connect to the Internet even though the phone showed full bars. As far as overall status indicators, the most obvious one was the phone showing “E” for very slow 2G “Edge” data instead of “4G”. I was not aware that there were still 2G Edge networks active anywhere in the world. Maybe there aren’t and the phone just showed that when it had a GSM signal rather than a 4G (LTE) signal. Eventually I checked the app that installed the eSIM and saw that the data allocation had been used up.

Yet Higher Power Consumption

Since we had only a couple of days left and plenty of data remaining on the other phone my work around was to share the connection from the phone with data remaining to the phone without. So the phone with data was providing WiFi hot spot functionality in addition to searching for non-existent US cellphone towers. That wasted the battery in a very short amount of time. It also used nearly 1 GB of data in a couple of hours (I really have to find out what is eating up data on that other phone).

Lesson learned: Only enable the “Personal Hotspot” if the phone is plugged into a charger or for very short periods of time.


The Apple Airdrop feature is very convenient for sharing photos, etc. with your fellow iPhone users. But it stopped working when the data eSIM was activated. When you tried to share a photo the person would show up as available via Airdrop but when you tried to send you just got a spinning wheel and a “waiting” message. Eventually I figured out that I needed to enable sharing with everyone on both phones instead of only with people in our contacts. It seems the phone number associated with the data eSIM confused Airdrop. I suspect that if we added the phone number associated with the data only eSIM into our contact entries for each other it would have worked but did not take the time to set that up and test it.

Since Airdrop asks the recipient if they want to receive the file or photo before it is actually sent it seemed safe enough to change the sharing option to everyone.

Even there, you were presented with two possible recipients one as listed in your contacts and the other based on the name of the phone. You had to select the one with the name of the phone for the transfer to actually work.

And Finally

The last glitch was at the end of the trip when I uninstalled the travel eSIM from each phone. The iPhone actually had to be rebooted to clear up all of the bits and pieces of the data eSIM configuration. Until that time the phone would show good status (full bars, LTE data, etc.) but would not actually connect to the Internet. Rebooting after removing the data eSIM resolved that problem.