You may not know it, but there are two different models of iPhone X that you can buy. No, I'm not talking about different storage sizes or colors; instead, there are two different cellular modems that distinguish the two models.
The A1865 model has a Qualcomm modem inside it and supports the networks of the four major wireless operators in the US. UU That's the version you'll get if you buy an unlocked phone without a SIM card directly from Apple, or if you buy the Sprint or Verizon versions.
The other model is A1901, which has an Intel modem and is sold by AT & T and T-Mobile. (Technically there is a third model, A1902, but it is only sold in Japan and is specially adapted to its cellular networks there.)
We've known for a long time that there are two different models of iPhone X, but the results we've been waiting for They only left last Friday. Tests conducted by Cellular Insights showed that the iPhone X powered by Qualcomm has an advantage over the model driven by Intel in LTE speeds in the most common LTE band. The difference is not huge, but it is detectable.
It is also likely that there are other differences not detected by that specific Cellular Insights test. Last year's iPhone 7 Plus also had Intel and Qualcomm models, and tests conducted at the time showed that Qualcomm's iPhone 7 Plus was much better at using a weak LTE signal than the Intel version.
Qualcomm modems have also historically been more energetic -efficient, so it's possible that the Qualcomm-modem iPhone X would see longer battery life, particularly when it comes to weak LTE signals, or pass signals of change of time, such as when driving on a highway. There is no evidence to support that yet, but it is a possibility.
The only thing we can say with certainty is that the best iPhone X to buy is the non-sim version, directly from the Apple website. It is compatible with Sprint, Verizon, T-Mobile and AT & T, and as you own it directly, you can take advantage of all these offers and switch between operators at will.
According to the initial tests, it also seems that it could obtain a marginal advantage in LTE speeds. The differences are small: Apple artificially limits Qualcomm's modem to the same type of performance as the Intel chip, but take the small wins where you can get them.