T-Mobile has been the target of much consumer ire in the past due to the way it throttles user bandwidth and tries to keep it a secret. If you regularly use the Internet on your phone, it's going to be obvious when the performance is less than what you're used to getting. For many, at the first sign of poor network performance, a website like Speedtest is visited in order to gauge whether it's just a download going slow, or the website you're on.
The problem T-Mobile customers faced was that Speedtest results would come back just as expected, with no degradation. In actuality, T-Mobile simply detects when these bandwidth testers are used, and then deliver full performance. With everything else, the user would have to suffer with frustrating throttled bandwidth, with no proof that they're actually dealing with it outside of their own usage.
As it happens, this behavior is effectively lying, and the folks at the FCC are not too happy about it - changes are going to be made. Going forward, T-Mobile (and other carriers) will be required to transparently tell their subscribers if their bandwidth has been throttled. Rather than fine T-Mobile, the FCC instead requires the company to begin informing its users when throttling happens, and also include a new app on customer phones to let them take advantage of an accurate speed test.
It's a little sad that the FCC had to step in here, and perhaps even more sad that T-Mobile thought that it could get away with this (well, let's be honest - maybe it's not that surprising). Admittedly, I am not really sure FCC's requirements of T-Mobile are enough. Given the deceit the company's guilty of, I think it would have been more apt to require it to message each and every one of its customers to lay its admission out on the table.
On the upside, an important change has just happened, so we have that to be happy about.