T-Mobile US, the country's fourth-largest carrier, is on the up-and-up, its Q3 2013 earnings revealed on Tuesday. The self-described "Un-carrier" posted increased revenue, decreased losses, and more customers as it works to shake up the mobile industry.

Specifically, T-Mobile reported $6.7 billion in revenues for Q3 2013, up 7.4 per cent from Q2 and 37 per cent from Q3 2012. Operating income sat at $297 million, up 64 per cent from Q2, but the company still posted a $36 million in net losses, though improving 33 per cent from Q2.

Read: T-Mobile USA reveals 'Jump' - a semiannual upgrade program for phones, launches 14 July

It added 1.02 million net customers during the quarter, making 45.04 million total customers at the end of the quarter. Its main T-Mobile and MetroPCS brands accounted for 678,000 of those customers. Q3 2013 customer performance was similar to Q2, with the company adding 1.1 million customers. 

The carrier sold 5.6 million smartphones in the quarter, or 88 per cent of total phone units, and up from 4.3 million in Q2. T-Mobile has been aggressive with its new UnCarrier approach. Under the UnCarrier plan customers do not have to sign a two-year contract, but instead pay full price for a handset at time of purchase or $149 (£65) up front with $20 a month in payments for the next 24 months.

Using the iPhone 5 as an example, that will round out to $619 over two years, or $20 cheaper than Apple's unlocked version. Once the payment period is up, the phone is unlocked and yours to take to any carrier.

“T-Mobile’s Un-carrier approach is resonating with consumers. We added more than 1 million customers and led the industry with 643,000 branded postpaid phone additions because we are fixing the things that drive customers crazy,” said John Legere, president and CEO of T-Mobile.

“Part of our customer momentum comes from the MetroPCS acquisition. With MetroPCS we are making great progress, including the planned additional expansion of the MetroPCS brand into another 15 additional markets by November 21.”

During an earnings call with investors, T-Mobile backed AT&T sentiments that iPad Air sales have been going well. The carrier said it sold more tablets on the iPad Air's launch last Friday than the entire previous quarter. T-Mobile has enticed tablet buyers with 200 megabytes of free data each month.