Exactly, Google will never add codes to Android KitKat that tells T-Mobile about unauthorized Tehtering.
/sarc
AFAIK, it doesn't. 4.4 contains a setting that allows a provider to specify a different APN for tethering use, which I can imagine is a legitimate feature. You can also turn it off (on IPv4 at least)
The same Nexus 4 + Android KitKat 4.4 + AT&T SIM Card does not detect unauthorized tethering.
Surprisingly this "feature" only appears when using T-Mobile SIM Card.
It is not the case with Android Jelly Bean 4.3
The nice thing about android is that you don't have to care what Google and your your Provider do in many cases, because the "jailbreak" is official: You can install CyanogenMod or even Replicant.
As opposed to Apple which just doesn't allow tethering on any networks.
You're right, sorry for not being more clear. What I intended to say was that Apple won't allow you to tether without approval on any networks. At least it defaults to allowing on all networks by T-Mobile.
Apple even respects T-Mobile's wishes on the matter.
I put a SIM connected to one of T-Mobile's $30/5GB prepaid accounts in my iPhone 5. When I try to turn the tethering function on, I get a prompt telling me to go to a T-Mobile website to get on a plan that supports tethering.
Ignoring the wishes of the people who gave them the better part of a thousand dollars for the piece of hardware in their hand.
The carrier control of tethering made sense back before the iPhone had market dominance. Now it's stupid and user-hostile.
That's just not even remotely true. What Apple does (to my annoyance) is allow the carriers to control whether or not the phone allows tethering. But they do allow it if the carrier does, and plenty of carriers allow it (usually after making you pay extra). I've been tethering with my iPhone on AT&T, officially, for years now.
Why would I buy into an ecosystem that then forces me to hope someone far smarter than I is able to break the security of that system for me? Jailbreaks are worrisome because they introduce a potential loss of security on mine, and all users phones.