What we know: Updated as of 10/09/2015 There are two different versions of the iPhone 6s (Plus). Differences emphasized in red: Model A1633/34 LTE (Bands 1, 2, 3, 4, 5, 7, 8, 12, 13, 17, 18, 19, 20, 25, 26, 27, 28, 29, 30) TD-LTE (Bands 38, 39, 40, 41) TD-SCDMA 1900 (F), 2000 (A) UMTS/HSPA+/DC-HSDPA (850, 900, 1700/2100, 1900, 2100 MHz) CDMA EV-DO Rev. A (800, 1700/2100, 1900, 2100 MHz) GSM/EDGE (850, 900, 1800, 1900 MHz) Model A1688/87 LTE (Bands 1, 2, 3, 4, 5, 7, 8, 12, 13, 17, 18, 19, 20, 25, 26, 27, 28, 29) TD-LTE (Bands 38, 39, 40, 41) TD-SCDMA 1900 (F), 2000 (A) CDMA EV-DO Rev. A (800, 1700/2100, 1900, 2100 MHz) UMTS/HSPA+/DC-HSDPA (850, 900, 1700/2100, 1900, 2100 MHz) GSM/EDGE (850, 900, 1800, 1900 MHz) AT&T and the SIM-free model use model A1633/34 Verizon, Sprint, and T-Mobile use model A1688/87 Apple has updated the iPhone 6s technical specifications page, indicating that both models will support CDMA. The only difference is the model A1633/34 is band 30 capable, while the other is not. This is additionally supported by the FCC documents showing that "all models have identical PCB layout, design and functionality except A1634 has Tx and Rx filter for Band 30." This should also quell any question if model A1688/87 will have band 30 support, which it most likely will not. I want to get an unlocked iPhone, so which model should I get? AT&T owns band 30 and is planning to expand out their 2.3GHz WCS LTE network in the future, which will offer impressive speed gains for AT&T users. If you plan on using the phone with the AT&T network in the future or in a different country on a network that supports the 2.3GHz spectrum between 2305MHz and 2360MHz, then you should consider getting the A1633/34 iPhone 6s. This is likely the "best" phone as it supports the most bands. A1688/87 lacks band 30 support, but for the vast majority of people, it is not a big deal. Band 30 is still being rolled out, and you likely do not live somewhere that will have it anytime soon. By the time it becomes relevant, the iPhone 7 will be coming out. tl;dr: The SIM-free A1633/34 is the "best" phone with band 30 support and whitelisting, but it is not significant for the iP6s' generation. Where is AT&T rolling out their WCS LTE network (Band 30?) AT&T has not disclosed what markets they are rolling out to yet. "AT&T did not specify which markets are gaining WCS coverage, nor how quickly it will build out coverage around the country. AT&T is, however, expected to start with markets that have more capacity requirements." - phonescoop.com (9/10/2015) Relevant reading: AT&T begins deploying 2.3 GHz WCS spectrum for LTE Is the iPhone 6s the Best Choice for Travelers? Beware: AT&T's iPhone 6s Limits Your Carrier Choices The iPhone 6s on Sprint and Verizon will be different models How to pre-order your iPhone 6s unlocked and contract-free from Apple iPhone Specs @ EveryiPhone.com AT&T Finally Using WCS Spectrum for LTE; Will Test LTE-U >>>Updated: AT&T Has a Faster iPhone 6s<<< Readers, help us update this post with the latest information! If you can deny, confirm, or add to any of the information on this topic, please post your source here and this information will be updated.