Unless you own a laptop or tablet with 4G connectivity, your mobile internet connection will likely be through your smartphone unless you're happy to pay for public Wi-Fi. Sometimes public Wi-Fi isn't available, though, so then what?

The good news is it's possible to use your smartphone as a portable Wi-Fi hotspot, and share its data connection with your Wi-Fi-only tablet or a laptop.

This setup is called tethering or internet sharing, and most smartphones provide this feature, including iPhones. It works in the same way as a mobile Wi-Fi router, but with no extra hardware required.

Once you've turned on tethering, any device with a wireless connection can connect to the internet via your iPhone's data connection.

Regardless of the connection method, it's important to check whether your mobile tariff allows tethering before using your iPhone as a Wi-Fi hotspot. In some cases, the mobile operator can prevent the option from appearing on your handset if tethering isn't part of the deal - iPhone owners will notice that Personal Hotspot simply doesn't show up in the General settings menu.

In other cases, it's physically possible to set up tethering but if it's disallowed on your tariff you could find yourself with a warning or even being cut off for breaking the rules. Some operators are more lenient than others, but always check if you're not sure.

You should also note that internet tethering quickly gobbles up data allowances and battery life on the host device, so be prepared with a power bank and remember to keep an eye on your data usage.

Set up an iPhone Wi-Fi hotspot

Share your iPhone's data connection with Personal Hotspot

• On your iPhone open the Settings app and choose Mobile Data (if you're using an older version of iOS this will come under Mobile)

• Select Personal Hotspot, then toggle the slider to turn it on

• You'll be prompted to turn on Bluetooth and Wi-Fi if they are off, and we recommend agreeing to this else your hotspot will be limited to USB

• Tap Wi-Fi Password and enter a password you will remember

• Take note of the name of the hotspot so you can provide others with both the Wi-Fi network name and password when they wish to get online using your connection

If you have an Android phone, see our separate guide on how to set up internet sharing on Android.

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