T-Mobile (TMUS 2.74%) has officially passed Sprint (S +0.00%) to become the United States' third-largest mobile carrier, but it's still well behind AT&T (T 1.22%) and Verizon (VZ 1.32%). T-Mobile has added over 1 million customers in each of the last nine quarters while Sprint is just barely treading water by adding tablet subscribers to make up for lost phone subscribers.
Here's how T-Mobile put Sprint in its rear view mirror -- and plans to continue grabbing customers from AT&T and Verizon.
