What Is Tethering a Cellphone?

Tethering turns your phone into a router for other devices

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Tethering refers to the use of a mobile device connected to the internet as a modem for a separate device, such as a laptop or Wi-Fi-only tablet. This approach offers internet access on the go, wherever you are. You connect your phone to your laptop or tablet either directly with a USB cable or without wires through Bluetooth or Wi-Fi.

Tethering Benefits

Tethering offers internet connectivity to devices that lack a built-in 3G or 4G mobile data plan. It's especially helpful in situations where no other means of internet access are available: when, for example, there's no Wi-Fi hotspot around, your cable modem goes on the fritz, or you're on a dirt road in the middle of nowhere and need an online map.

If you're already paying for data on your cell phone and your wireless provider doesn't require any extra fees for using your cell phone as a modem for your laptop, tethering can also save you money, since you won't have to pay for separate mobile broadband service or buy additional hardware just to get your laptop connected.

You can also browse the web more securely using a tethered phone, because your information is being sent directly through the phone versus, for example, over a public open wireless hotspot.

Finally, tethering can help you conserve laptop battery power because you can turn off Wi-Fi on your laptop while you use your phone as a modem.

Tethering Drawbacks

Using your phone's data service for your laptop will drain the phone's battery more quickly, especially if you're using Bluetooth to connect your phone and laptop. Tethering through USB would be a better way to connect than doing it wirelessly because of the battery drain.

If you can't get a cable sync to work, you should confirm that your USB port is working correctly.

The speed of a tethered device may not be as fast as you would expect, even on the phone itself, because the information has to take that extra step over the air or through the wire. USB connections will generally be faster than Bluetooth. If you're using 3G, upload and download speeds will typically be less than 1 Mbps. If you're in an area not covered by mobile broadband, you'll likely get speeds only a few times faster than dial-up.

Depending on your particular phone and connection method, you also may not be able to use your voice service on the phone while it is tethered.

The biggest obstacle, however, is whether you can tether your phone to your laptop at all. Each wireless carrier has different rules and service plans for tethering, and each cell phone device may have its own limitations. How to tether your cell phone largely depends on your cell phone service provider and your cell phone model. The major wireless carriers in the United States are now charging extra monthly fees just to tether your phone or use a phone as a Wi-Fi hotspot for more than one device to get online.