What is Uncarrier 12 and why is T-Mobile offering unlimited data?

T-Mobile's latest Uncarrier move is less about thanking you and more about increasing its monthly revenue.

The company has announced that it is moving all postpaid plans to a so-called T-Mobile One scheme, getting rid of data buckets in favor of a single account type that includes unlimited, calls, text, and data, along with all the other Uncarrier benefits previously announced such as low-cost roaming, weekly perks, and low-friction carrier switching.

Starting at $70 per month for the first line, $50 for the second line, and $20 for all others up to a total of eight per account (amortized to about $40 per person for a family of four), T-Mobile One lets users consume as much data as they want without incurring overages. While T-Mobile already offers rollover data (an earlier Uncarrier promotion) of up to 20GB per month, this gets rid of all that bean counting. Customers can also add a tablet to their accounts for $20 each (at 4G LTE speeds), and a cellular wearable such as a smartwatch for $5 per month (at 2G speeds). The above prices are also limited to customers paying with pre-authorized credit cards; add $5 per month if you want to pay manually.

There are some caveats here, though: slow tethering, and low-quality video

There are some caveats here, though: T-Mobile One doesn't extend to video, at least not in the high definition sense. As part of another previous Uncarrier move, T-Mobile already zero-rates video from a number of providers, including Netflix and YouTube, but only at a resolution of 480p. This still stands: video being the bulk of a network's capacity at peak hours, T-Mobile is charging an additional $25 per month per line to lift that 480p limit. It appears that all video will be streamed at SD quality while over 4G LTE under T-Mobile One, with no option for a toggle to lift that restriction. Higher-quality video will be available on Wi-Fi.

The other issue is that T-Mobile One only offers Wi-Fi hotspot support at 2G speeds. This is understandable, as the company doesn't want users blasting high-speed wireless to dozens of other devices and gumming up the network. High-speed tethering is possible — at $15 per month per line for 5GB of LTE data. Previous T-Mobile plans included LTE tethering, including the former incarnation of the (albeit more expensive) unlimited plans, up to a maximum of 14GB per month.

Finally, T-Mobile will still be throttling the top 3% of data consumers which, according to an in-house data sheet, is those using 26GB of data per month. Once that level is hit, a user will be throttled to 2G speeds.

T-Mobile One rolls out starting September 6, and existing customers will have the option of transferring to the new plan with no penalty — but for the inevitable price increase.