Will U.S. mobile device sales take a big dive?

(MoneyWatch) Much of the tech economy has become obsessed with mobile, whether smart watches or apps to help you find a parking space. Why? Because the sales and use of mobile devices, particularly in the U.S., has kept a burning pace to the delight of such companies as Apple (AAPL) and Google (GOOG). And to the so far bitter disappointment of Microsoft (MSFT) and others who have fared less well.

That domestic pace may be about to slow, according to management consultancy cg42. A survey of 2,500 members of the U.S. population and 1,000 people intending to buy a mobile device in the next year suggests that the rate at which people will upgrade devices is slowing. It also suggests that while Apple leads in terms of most favored brand for next purchase, the percentage of people undecided is just as large.

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According to the study, only 16 percent of U.S. respondents planned to buy a new mobile device in the next 12 months. If that number is representative of the population as a whole (always a question) and covers only such intelligent devices as smartphones, tablets, and wearable computers, that would mean at the most 48 million devices sold domestically across all vendors and types. To compare, the IDC forecast for 2013, published in April, was 137.5 million smartphones alone in 2013.

That would represent at least a 65 percent drop in the pace of sales, which seems unlikely. Either this study has significantly underestimated future sales or the mobile market could be in for a startling slowdown.

The survey also asked which type of device likely buyers would favor. Apple was tied for first place with 34 percent. The other choice was undecided. Android as a category came in next at 27 percent, with Microsoft at 3 percent and troubled BlackBerry (BBRY) at 2 percent.