Sharing a device's cellularly connected internet to nearby devices is called tethering.
Tethering, or phone-as-modem (PAM), is the sharing of a mobile device's Internet connection with other connected computers. Connection of a mobile device with other devices can be done over wireless LAN (Wi-Fi), over Bluetooth or by physical connection using a cable, for example through USB.
If tethering is done over WLAN, the feature may be branded as a personal or mobile hotspot, which allows the device to serve as a portable router. Mobile hotspots may be …