Many modern smartphones allow you to connect to the mobile data network (3G) & then act as a WiFi router providing internet access to nearby devices.
Rather than carry an internet dongle with its own SIM & mobile data account, you can use the data plan on your existing mobile phone. Any WiFi enabled computer or tablet can connect to it, & since the Wi-Fi router is inside your phone, there’s no extra stuff to carry with you & no other device to recharge. However, make sure you monitor your usage to avoid excess data charges.
Setting up a mobile hotspot is easy. Most smartphones come with an app that allows the phone to act as a WiFi hotspot. The details vary based on the phone in question, but after clicking a box to turn the hotspot on, you’ll typically configure it for the first time by typing in a network name, choosing its encryption type and designating a security password.
Connecting to the hotspot is the same as connecting to your home or office Wi-Fi router. The network name shows up on the Wi-Fi connection screen, & you are required to type in the network’s password the first time you connect. After that, you can set it up to connect automatically.