It said 1.75 billion handsets had been bought, marking a 1.7% decline. Analysts at the firm suggested "tough economic conditions" had been partly responsible for the drop. It follows official data from Spain indicating its number of mobile telephone and datacard subscriptions fell by 5% over the same period.
A report by the Spanish regulator CMT said there were nearly 2.8 million fewer such contracts at the end of the year than at the beginning, with Telefonica's Movistar unit and Vodafone bearing the brunt of losses in December.
The country's gross domestic product (GDP) shrank by 1.3% in 2012, according to its central bank.
Gartner's data suggests weakening demand for feature phones - lower-end devices with limited functionality - led to the drop. It said that in the final three months of the year, 264.4 million such devices had been sold - 19.3% fewer than over the same period in 2011.
Although smartphones had seen a 38.3% year-on-year gain over the fourth quarter, they had still remained in the minority with 207.7 million units sold, the study said. The firm added that Apple and Samsung had dominated the smartphone market, with a combined 52% share in the October-to-December quarter.
Source: BBC News
