The best way to find out if an Indian Samsung phone will connect to USA networks is to see if that model is also being sold in USA at the time of purchase. Usually, the top of the line models like the S series and the top A series should be OK. If not, chances are that your new phone WILL NOT connect to USA networks. In Dec 2019 I purchased an M30s, an excellent midrange phone. Works great in India but it won't connect to any USA network. I tried every possible **bleep** I could that I found on the web, but to no avail. I took out the Airtel SIM and put it in my American Galaxy S10 and I got excellent connection through AT&T. So: Buyer Beware. Neither Samsung nor any sales person will warn you about this.
It is known that samsung phones do not work well when the phones are operated in another region. Samsung has been doing this for some time and people have been complaining. For international traveling iphones are better since they do not exhibit this behaviour
