Originally Posted by
gfunkdave
The CDMA/GSM split stopped really being a thing with the advent of LTE. Verizon and Sprint still operate their legacy 2G/3G CDMA networks, but LTE is LTE.
Whilst this is true, the problem has now moved (more than before) to the issue of band (frequency) support. This always existed (especially in the GSM world), but it's a bigger problem with LTE when it comes to cross-provider/country support.
Originally Posted by
gfunkdave
As an example, AT&T use LTE uses Bands 2, 4, 5 and 12/17 depending on the area. The only cross-over between AT&T and that device is band 5. So whilst this will work on AT&T in some areas, it won't necessarily work everywhere or with great performance depending on the availability of band 5.
T-Mobile use LTE bands 2, 4, and 12, so this device will not work on T-Mobile at all.