AIRSIM

What Happens the Second You Open the AIRSIM App

You install the app, open it, and the first thing you see is a login screen. But you do not have an account yet. The app asks for your AIRSIM card number or eSIM registration. That is the first moment of friction. You cannot do anything without that physical card or eSIM QR code. The app is useless on its own.

Once you have the card, you scan the ICCID. The app pulls up your account balance and shows you a list of countries. You pick your destination and a date range. Then you buy a package. The payment goes through Google Pay or a credit card. After that, you wait until you land. The OTA technology is supposed to switch your SIM to a local network automatically. But if you buy the package and do not travel immediately, the package sits there unused. The clock does not start until you arrive. That is a helpful detail.

How the OTA and Package Selection Work Together (or Against Each Other)

Here is where the design gets interesting. The OTA technology is the core promise. It configures the SIM to act like a local card in over 130 countries. You do not need to swap physical SIMs. But the app also lets you pre-purchase a package for a specific country. If you buy a Japan package and then travel to Thailand instead, that package is wasted. You cannot transfer it. The OTA technology does not automatically change the package. It only changes the network profile. So you have to select the correct destination in the app before you buy. If you forget, you are stuck.

This creates a workflow where you must decide your itinerary before you leave. The app does not offer a global plan that works everywhere. Each country or region has its own pricing and data limits. For example, the Japan unlimited plan costs around HK$10 per day, but the Europe plan might be different. You have to check each one separately. This is not a problem for a single-destination trip. But for a multi-country journey, you need to plan each leg carefully. The app does not combine packages or offer a discount for multiple countries. You pay full price for each.

Real-World Performance: Ads, Bugs, and Smooth Operations

Once you are on the ground, the app itself runs smoothly. There are no intrusive ads. The interface is clean and straightforward. You can see your remaining data and the package expiry date. The speed depends on the local network. In Japan, tests show speeds over 200 Mbps in some areas. In other places, like China, users report that the signal is poor and many apps do not load. That is not the app's fault directly. It depends on the local roaming partner.

The biggest bug reported is the OTA activation failing. Some users say they arrive and have no data. They have to contact customer service. The app provides multiple support channels: WhatsApp, WeChat, Facebook Messenger, and a hotline. The response time is advertised as within 1 minute. But some reviews say it takes longer. The app also has a known issue where old SIM cards stop working after an update. The changelog says "Bug fixed, new function added" but does not specify what was fixed. This lack of transparency is a recurring complaint.

The app does not crash often. It is stable on Android 7.1 and above. The download size is around 60 MB. The permissions requested are minimal: phone, storage, and location. These are standard for a roaming app. The app does not drain battery excessively. It runs in the background only when you check data usage.

APN Settings and Manual Network Selection

If the automatic OTA fails, you have to go to your phone's settings and enter the APN manually. The app's website provides two APN values: "kroly" and "rh". You select the correct one based on your destination. You also have to enable data roaming and manually select a network operator. This is not described in the app itself. You have to find it on the website. The app does not guide you through this process. It just shows a generic error message. This technical detail is the final piece of the puzzle. If you cannot get the APN right, you have no data. The app ends there.