Telefonica El Salvador APN Settings for ZTE Grand S3

Open App Drawer and go to Settings Mobile network settings Access point names

Press ➕ button on top right corner.

Enter name: Telefonica
APN: internet.movistar.sv
Proxy:
Port:
Username:
Password: movistarsv
Server:
MMSC:
MMS Proxy:
MMS Port:
MCC: (keep the default value set by phone)
MNC: (keep the default value set by phone)
Authentication type:
APN type: default

Keep default values for all blank fields shown above.

Press menu button (top right) and select Save. Done.