I have an unlocked Android - a Samsung Galaxy Golden, actually (which does not have a forum/much information online in general), but have been scouring information about other Samsung Galaxies due to a lack of information about my rather rare model. I bought it unlocked, and connected it to AT&T. I changed the APN settings so that it connected to the AT&T 3G network (H+) but I can't get it to connect to the 4G LTE network. Here are the settings I am currently using (which allegedly connect Galaxies to the LTE network):
Name: ATT HSPA+
APN: phone
Proxy: <Leave in Blank>
Port: <Leave in Blank>
Username: <Leave in Blank>
Password: <Leave in Blank>
Server: <Leave in Blank>
MMSC: http://mmsc.mobile.att.net
MMS proxy: proxy.mobile.att.net
MMS port: 80
MCC: 310
MNC: 410
Authentication type: <Leave in Blank>
APN type: default,supl,mms,hipri
APN Protocol: default
Bearer: default
Name: ATT HSPA+
APN: phone
Proxy: <Leave in Blank>
Port: <Leave in Blank>
Username: <Leave in Blank>
Password: <Leave in Blank>
Server: <Leave in Blank>
MMSC: http://mmsc.mobile.att.net
MMS proxy: proxy.mobile.att.net
MMS port: 80
MCC: 310
MNC: 410
Authentication type: <Leave in Blank>
APN type: default,supl,mms,hipri
APN Protocol: default
Bearer: default