To turn a mobile phone into a free Wi-Fi hotspot, one needs to have access to a mobile Internet connection. This usually comes with a charge from the network provider.
On an Android phone, navigate to "Settings," and then "Tethering and Networks." Tap the "Wi-Fi Hotspot" switch and choose a password. Wi-Fi devices such as laptops and other mobile phones can now connect to the network using the password.
To hotspot an iPhone, tap "Settings," then tap "Cellular." Tap "Personal Hotspot" to switch it on. Configure the hotspot. Now, any Wi-Fi-enabled device can connect to the network. To connect to a Wi-Fi hotspot, one should perform the same procedure as he would to connect to any Wi-Fi network.