From smartphones to tablets to Wi-Fi hotspots, Americans are toting around almost 400 million wireless connected devices, or more than 1.2 per person on average.
And they’re on those devices more than ever, whether posting Facebook (fb) updates, catching a movie on Netflix (nflx), or just making a plain old phone call. Mobile data usage exploded 42% last year to 13.7 trillion megabytes, according to the latest statistics from CTIA, the wireless industry trade group. That’s 35 times the amount of data used in 2010 and enough bandwidth to stream 1.6 million high-definition movies, the group adds.
The mobile boom has bolstered the revenue and profits of wireless carriers like Verizon (vz), T-Mobile, and AT&T for more than a decade. But the market is now posing a challenge as subscriber growth slows and usage continues to skyrocket.
Somehow, the carriers must keep increasing the capacity of their networks while fighting over a shrinking pool of new customers. The result, at least so far, has been fierce competition and price cutting on unlimited data plans—a big win for consumers. Service revenue for wireless plans slipped 2% to $188 billion, the second decline in the past three years, CTIA said. And carrier sales of phones and other equipment also dropped 2% to $47 billion.
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The next act, however, might bring greater consolidation, which could lead to higher prices.
On Wednesday, Sprint’s (s) majority owner and Japanese billionaire Masayoshi Son said he still hopes to merge with T-Mobile. Under the Obama administration, Son’s effort to buy T-Mobile (tmus) was blocked, but the Trump administration has proven much friendlier to big telecom companies so far. T-Mobile CEO John Legere and Verizon CEO Lowell McAdam have also talked mergers lately. AT&T (t) is going another direction with its big media plays.
With limited airwaves, one way the carriers have been trying to cope with massive data growth is by adding more cell tower transmitters, some as small as a shoebox that can be affixed to light posts and traffic signals. A record 308,334 cell sites were in operation by the end of 2016, CTIA said, a 9% increase over the past five years.