In order to understand how users will hide their tethering usage, we have to understand why unofficial tethering on Android isn’t taking the same heat from AT&T as iPhone users. Hiding Unofficial iPhone Tethering Usage, or, How to Be Like an Android User In other words, AT&T simply looks at who is using tethered data through these APN’s, and then they cross-check these user accounts to see if they’re paying for a tethering plan. This makes it extremely easy for AT&T to identify whether or not an iOS device is utilizing tethering, and just how much of their data is consumed via tethering. This method exposes tethering activity quite readily, because the iPhone, when in tethering mode, sends traffic through an alternate APN (AT&T access point/router) for the express purpose of identifying the traffic as tethered data. Jailbroken iPhones typically use the same tethering technique as a standard iPhone, the one that’s already present in iOS. So how does AT&T know you are tethering in the first place? Apparently it’s very easy to detect from iPhone users, as AndroidPolice explains:

How AT&T Detects Unofficial Tethering from the iPhone

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