Sprint's ongoing efforts to revitalize its business aren't looking too shabby, for now. The mobile carrier's most recent earnings show that the company added 501,000 postpaid subscribers with a churn rate of 1.62 percent — its lowest ever for a third quarter, and its best year-over-year improvement in 12 years. However, the company is still lagging behind the market's leaders, like T-Mobile and Verizon, with the latter adding 1.5 million postpaid subscribers in the same quarter, with a churn rate of just 0.96 percent.

There were still substantial losses of $836 million on operating revenue of $8.1 billion (compared to a net loss of $2.4 billion for the same period in 2014), but the company was able to raise its financial outlook for the year. Instead of predicting earnings for the current fiscal year in the range of $6.8 billion to $7.1 billion, Sprint has now upped this to between $7.7 billion and $8 billion.

Sprint, and its parent company SoftBank, are still on a difficult mission to cut costs and improve its network quality. Just yesterday it was reported that the fourth-place carrier would be laying off 2,500 employees — mostly from its customer service call centers. Sprint's ambitious plan is to cut $2.5 billion in costs while also raising its network quality to first or second place in the US — difficult goals to square.