The most important smartwatch usability factor in my opinion is whether the smartwatch has LTE. In 2018, only four Wear OS watches had LTE. The low relative adaption rate of Wear OS despite its usefulness, in my opinion, is due to lack of LTE in all watches except one until 2017.
Project Fi and Ting work with Wear OS smartwatches having LTE, using the T-Mobile network. AT&T also works with Wear OS LTE smartwatches. The overlapping T-Mobile/AT&T LTE bands with Wear OS include bands 2, 4 and 5 depending on your watch.
LTE smartwatch comparison
|Model||CPU||LTE Bands||Project Fi/Ting|
|LG Urbane 2nd Ed. LTE LG-W200A||SD 400||2, 5||Yes|
|LG Urbane 2nd Ed. LTE LG-W200V||SD 400||13||No|
|LG Watch Sport LG-W280A||SD 2100 MSM8909W||2,4,5,13||Yes|
|Verizon Wear24||SD 2100||13||No|
|Huawei Watch 2||SD 2100||1,3,7,8,39,41||No|
|Apple Watch 3 LTE A1860/A1861||2,4,5,12,13,17,18,19,25,26,41||No (eSIM)|
Why not Apple Watch LTE?
The Apple Watch is not currently compatible with Project Fi/Ting since it uses an eSIM and Project Fi/Ting currently require a nano-SIM.
Why are LTE bands important for smartwatches?
The LTE bands are important for knowing if the watch would work on a particular carrier. Sometimes a watch has LTE bands the carrier doesn’t and vice versa. As long as one or more LTE bands overlap, your watch might work–always double check before making a purchase! Carriers don’t use all their authorized LTE bands throughout their entire network. Some LTE bands are used only in urban areas, particularly the higher frequency LTE bands such as Band 41 for the Huawei Watch 2.