What just happened? Which smartphone do you think would top a US customer satisfaction survey taken in 2020? Could it be Apple's best and most expensive iPhone to date, the iPhone 11 Pro Max? Perhaps it's Samsung's tech-packed flagship, the Galaxy S20 Ultra? No, it's the Galaxy Note 9, a phone that launched back in 2018.

The surprising revelation comes from a survey carried out by the American Customer Satisfaction Index (ACSI). It asks participants to rate their phone based on several factors, including battery life, design, features, audio & video quality, software, and more.

Surprisingly, the list is topped by the Galaxy Note 9. While it remains an excellent handset, there have been plenty of newer devices released since its 2018 launch, including its successor, the Note 10, the Galaxy S10, and the iPhone 11 series.

The Note 9 topped the list with a score of 85 and was rated best in class for phone features and video quality. Samsung also took joint-second place with the Galaxy S9+ and the Galaxy S10, which both scored 84. The highest Apple entry, meanwhile, was the iPhone XS Max, which was also rated 84, while its iPhone 11 Pro Max flagship was further down the list with 82.

It's interesting to see both Samsung and Apple's older phones beat the newer models when it comes to customer satisfaction. It could be that some consumers feel the latest devices with their huge price tags should offer more for the money, or perhaps they just feel their predecessors were simply better.

While Samsung topped the list for individual phone models, the South Korean firm was beaten by Apple when it came to overall customer satisfaction. After both companies tied at an 81 percent rating last year, Apple has edged ahead to beat its rival by one point with 82 percent. LG came third with 79 percent, while Motorola was fourth on 77 percent.

Despite the fall in sales caused by Covid-19, general customer satisfaction with smartphones was up 1.3 percent year-over-year. US carrier services were also ranked in the survey, with T-Mobile coming top (76 percent), beating Verizon, AT&T, and US Cellular. Sprint came in last with 66 percent.