T-Mobile is the second-largest U.S. wireless carrier, serving roughly 142 million postpaid and prepaid customers. T-Mobile provides mobile voice, text, and data services under multiple brands — T-Mobile for postpaid, Metro by T-Mobile and Mint Mobile for prepaid — and sells through its own retail stores, the T-Life app, and third-party retailers. Postpaid accounts for roughly 81% of service revenue, prepaid around 15%, with the remainder from wholesale and MVNOs. T-Mobile's core business model is a monthly subscription for wireless service; the primary revenue drivers are account growth, ARPA (average revenue per account), and churn. Devices are sold on 24-month installment plans but are largely a pass-through; the high-margin recurring service subscription is where T-Mobile makes its money. Beyond core wireless, T-Mobile has built a fixed wireless access (FWA) home broadband business with nearly 8 million customers, running on excess 5G network capacity with minimal incremental capex. T-Mobile is also building a fiber broadband business through JV partnerships with Lumos and MetroNet. T-Mobile differentiates on a "no trade-offs" value proposition — pricing structurally below AT&T and Verizon while arguing its network quality is now comparable. Growth priorities include closing the network perception gap, expanding in small and rural markets, growing enterprise wireless, and scaling broadband to 18-19 million customers by 2030. Adjacent businesses — digital advertising, financial services, and AI/edge compute — remain small today.