Today, I’m going to share the simple way Chubby mom’s family used mobile data while traveling abroad. (Drumroll, please...!!!) The answer is... using a local SIM card during the trip! (Hehe 😝)
Curious, aren’t you??? Super curious, right??? Then gather around and keep reading!!!

But just a heads-up—there are actually many different ways to use mobile data overseas these days, not just the SIM card method I’m introducing today. So I recommend looking into the various options, comparing them, and choosing the one that works best for you! Just remember: this is simply the method that Chubby mom’s family personally prefers. 😉
Since we don’t get to travel that often, I’m also writing this down so we won’t forget how to do it next time… Definitely not a secret reason, nope, not at all! 😂
Alright then—let’s start with where we usually buy our SIM cards! (Not an ad, seriously! We paid for everything ourselves!!)
The SIM card our family always goes with is the Maltok SIM. It seems to be a pretty well-known company that sells overseas data products. If you search “말톡유심” on Naver, their website shows up right at the top. When you click into the Maltok homepage, there’s a menu bar at the top where you can choose the country where you’ll be using data.
Since Chubby mom’s family just got back from Japan, I’ll walk you through the Japanese SIM card option specifically. When you select Japan on the site, you’ll see a list of available products like the one below. We chose the SoftBank SIM, which is listed first and marked as the most popular option. It’s said to work throughout all regions of Japan, so it seemed like the best choice for us!
Since we were going on a 4-day, 3-night trip and didn’t expect to use a ton of internet (plus we had free Wi-Fi at the hotel), we chose a plan that still offered plenty of data—3GB per day at 5G speed (AW plan)—just to be safe. We purchased it for 4 days.
As shown below, you can choose where to receive your SIM card…!!! You can either have it delivered to your home or pick it up at Incheon Airport (both Terminal 1 and Terminal 2!!)
The price? Just 8,800 KRW for 4 days!
Since Chubby mom’s family always likes to prepare in advance, we had plenty of time—so we chose the home delivery option and received the SIM card at our house.
Also, as you’d expect, the price varies depending on the number of days you’ll be using it. (Makes total sense, right? 😄)
When the Maltok SIM arrives, it’s super easy to open—it tears open cleanly like this! As you can see in the photo below, it also comes with a small storage pouch to keep your original SIM card safe, and a SIM pin tool for swapping out the cards. So convenient!
After purchasing from Maltok, if the SIM card you bought requires activation by registering your departure date, you’ll receive a notification from Maltok via KakaoTalk. Just follow the instructions in the message to register your activation (departure) date.
However! For the Japan Maltok SIM that Chubby mom’s family bought, we got a KakaoTalk message that said: “This SIM will activate automatically upon insertion. No need to register your departure date.”
Thanks to that, we were able to use it right away without going through any extra steps—super easy!
[ Replacing the SIM Card and Using It Overseas on an iPhone!! ]
1. First, turn on Airplane Mode on your phone!
Just like in the photo, tap the airplane icon so that it lights up orange—this means it’s activated.
Chubby mom’s family usually switches to Airplane Mode while still on the plane, and then proceeds with step 2 about an hour before landing.
2. Then, turn off your phone completely.
3. Next, use the included SIM ejector pin to open the SIM tray and replace the SIM card.
Be sure to keep your original SIM safe by storing it in the provided storage pouch.
4. Turn your phone back on. (Don’t worry—Airplane Mode will still be on.)
5. Go to Settings > Cellular > Cellular Data Options and turn on Data Roaming. (Don’t worry—Airplane Mode will still be on.)
6. After the plane lands, turn off Airplane Mode. (Once Airplane Mode is off, cellular data will automatically turn on, so you don’t need to do anything else.)
7. After that, a popup might appear asking for permission—just tap “Allow” to enable data usage. And that’s it!!! Super easy, right???
Alright, next up—let’s learn how to replace and use a SIM card on a Galaxy phone abroad! (Let’s gooo!!!)
[ Replacing the SIM Card and Using It Overseas on a Galaxy!! ]
1. First, turn on Airplane Mode on your phone!
As shown in the photo, tap the airplane icon so that it lights up white—this means it’s activated.
Ttung-i’s mom’s family usually switches to Airplane Mode while still on the plane and then starts step 2 about an hour before landing.
2. Follow the same steps 2 to 4 as with the iPhone: turn off your phone, replace the SIM card, then turn your phone back on.
3. Go to Settings > Connections > Mobile Networks > Data Roaming and turn on Data Roaming. (Don’t worry—Airplane Mode will still be on.)
4. After the plane lands, turn off Airplane Mode. (Once Airplane Mode is off, Mobile Data under Data Usage will turn on automatically, so no further action is needed.)
5. Then, if a popup appears asking for permission, just tap “Allow” to enable data usage. And that’s it!!! Super easy here too, right???
Ta-da! It’s just that easy!! (Feeling a little shy here 😅)
If you’re planning to use a SIM card for data on your next overseas trip, I hope this info helps you out! (Pretty please!) And of course, I hope Ttung-i’s mom doesn’t forget how to swap SIM cards on her next trip…
Alright, that’s it for today’s post!
Sending 20,000 kisses... chu chu... 💋💋

Oh, and one more thing!!!
If you’re curious about another must-have item for Japan travel—a coin purse—or want to hear more about our Japan trip, check out the link below~!! (So kind of me!!!)
[“A Family Trip to Japan… and the Secret Weapon: A Coin Purse?!” ]
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