If your Wi-Fi is too slow and cellular data is erratic, there is an alternative. With an Ethernet cable, and the right adapter, you can connect your mobile device to an Ethernet port on your router or modem for a fast and dependable connection. It may seem odd to connect a mobile device via Ethernet, since Wi-Fi is built-in and easily available, but there are times when it makes sense. Your home Wi-Fi could be weak but your Ethernet connection is strong. You could be staying at a hotel with Ethernet port access, but unreliable or expensive Wi-Fi. Or you might need a better connection for online mobile gaming.