Samsung kept it hush-hush, but the new Galaxy Note7 is the first commercial device with 4×4 LTE MIMO thanks to Qualcomm’s X12 modem.
It’s currently disabled, perhaps waiting for testing to be complete before being enabled via an update. Also, 256 QAM may be enabled by such an update, pushing up to 33% more bits over the same number of megahertz. Combined, these will give the Note7 better reception and faster connection speed.
There are a few « ifs » to go along with that. Obviously, this is for the Snapdragon 820 model. The Exynos 8890 may only support 2×2 MIMO. Then again there’s your carrier – T-Mobile in the US has some towers with 4×4 support, but overall it’s rare. One place where you can try it is the Times Square T-Mobile Flagship Store. AT&T and Verizon aren’t there yet – you can read an in-depth article on the state of LTE Advanced in the US here.
It goes without saying that this is just speculation for now, Samsung hasn’t officially said anything about 4×4 MIMO.