For connecting your device to internet, APN (Access Point Names) setting must be configured at UE side to match ORS setting.
Example on Samsung S5 device:
• Go to Settings/More networks/Mobile networks
• Turn on Data roaming
• Go back to Mobile network.
• Add the first APN with the following parameters:
If everything is fine, there will be a 4G signal on your phone interface and you will be able to surf the internet freely.