U.S. smartphone growth dipped below 10 percent last year

It's not just China that is seeing a slowdown in smartphone growth. Here in the U.S., overall smartphone growth fell to less than 10 percent for the first time since the start of the mobile revolution.

That's according to an annual study by the mobile trade group CTIA, which also found that minutes of phone use and text messaging barely inched higher in 2015.

The one statistic that did show massive year-over-year growth — mobile data use — is something of a given and necessitates huge capital spending by carriers even as monthly bills remain roughly flat. On that front, Americans consumed 9.6 trillion megabytes of data, up from 4.1 trillion megabytes in 2014.