A:AnswerBT (Bluetooth) makes you phone able to access the information on the watch and use your watch to access the data and cellular services of your phone.
* Both "LTE" and "BT" versions support BT. *
LTE (Long Term Evolution) aka 4G/5G allows your watch to act as a cell phone and connect -directly to- your mobile service provider. For example: You can leave your phone at home while hiking or at the gym and still make and answer phone calls as well as use your phone's data plan.
* A standard "BT only" watch cannot do any of these things without being connected to WIFI or to your phone via BT. *
A:AnswerYes, it usually will sync with your phone on wifi during set it up. If you choose the LTE version you can set it up with a line from your phone company also to be able to make calls/text even if you arent near your phone.
A:AnswerI looked at both and settled in the Galaxy Watch 5 and have zero regrets. I love the ability to change watch faces, the features and compatible apps, and the battery life.
