# APN (Access Point Name)

> The setting that tells your phone which gateway to use on a mobile operator's data network; a wrong or missing APN means signal but no mobile data.

Source: https://viasimo.com/glossary/apn/
Also known as: Access Point Name, APN settings

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An APN (Access Point Name) is the setting that tells your phone which gateway to use when connecting to a mobile operator's data network. If the APN is wrong or missing, your phone can show full signal and still have no internet, because it does not know where to send data traffic.

Every mobile data connection passes through an operator gateway, and the APN is simply that gateway's name, such as internet or globaldata. It is not an account, a password or anything personal; every customer of a given operator typically uses the same APN string. On most phones the value is written automatically when an [eSIM profile](/glossary/esim-profile/) installs, so the majority of travellers never see it.

When it does need attention, the pattern is recognisable: signal bars are present, calls may even work, but web pages will not load. Android phones are the usual culprits, since some models fail to apply the pushed APN. You can check it under Settings, then Mobile network or Connections, then Access Point Names; on an iPhone it lives under Mobile Data, then Mobile Data Network. Enter exactly the value your provider specifies, save it, then toggle flight mode on and off. Our [eSIM troubleshooting guide](/magazine/esim-not-working-troubleshooting-guide/) puts this in a full checklist, and the [Android eSIM guide](/magazine/esim-for-android-complete-guide/) covers where the menu hides on the major brands.

A common confusion is blaming the APN too early. If mobile data fails, check first that the travel eSIM is set as the data line and that [data roaming](/glossary/data-roaming/) is switched on for it; those two settings cause far more problems than APNs do.

A concrete example: a traveller lands in Bangkok, installs an eSIM and sees signal but no data. She types in the provider's stated APN, restarts the phone and is online within a minute. If nothing works after that, [support](/support/) can confirm the correct value for your plan.