The duopoly continues. More than 90 percent of phones sold at each of the four major US carriers' stores in December were either Apple or Samsung devices, according to a store survey done by analysis firm Wave7 Research.

Apple and Samsung together sold 94 percent of phones at Verizon stores, 95 percent at AT&T stores, 94 percent at Sprint stores, and 91 percent at T-Mobile stores, according to the report. The most popular phone at all four carriers in December was the iPhone 11, the firm says. The top-selling Samsung Phone was the Galaxy S10.

We've reported on this duopoly many times before; it isn't news, but it's always startling to see how it continues. Analysts have told me several times that carrier stores control around 85-90 percent of US postpaid phone sales, meaning that Wave7's numbers are a good signal for what's happening at the higher end of the US phone market.

Some of the buzziest brands with the loudest fan bases are actually quite small in our market. Google's Pixel lineup was at 2-4 percent at each of the four carriers, while OnePlus came in at 2.3 percent overall thanks to the launch of the OnePlus 7T Pro McLaren at T-Mobile.

For people who like competition, there's a bright spot in prepaid, where fewer people buy $1,000 iPhones. Four out of the top five phones at Boost in December were iPhones or Samsungs, with the fifth being the LG Stylo 5, the report says. At MetroPCS, Samsung, LG, and Motorola were the top sellers during the first half of December, according to the Wave7 report.

According to Evercore via Fierce Wireless, in Q3 2018—the latest I could find data for—there were 46 million prepaid subscribers in the US and 267 million postpaid subscribers. Prepaid subscribers don't often enter the handset conversation in US media, though, because they don't generally buy high-end phones and typically have lower median income than postpaid subscribers.

Counterpoint Research combines prepaid and postpaid numbers to make things look significantly better for LG. During Q3 2019, Counterpoint says that Apple and Samsung together took 67 percent of the overall market, with 12 percent going to LG, 8 percent to Motorola, and 13 percent to all others.

This all makes the US market far different from other global markets, Counterpoint notes. Globally, the top five vendors in Q3 2019 were Samsung, Huawei, Apple, Oppo, and Xiaomi, the firm says. Three of those—Huawei, Oppo and Xiaomi—don't even play in the US market at all, and have no concrete plans to. Huawei is effectively illegal in the US because of political concerns. Oppo recently told PCMag that the US is the "most difficult market in the world," while Xiaomi has several times said it was thinking about launching here, and then backed out of those plans.