Most laptops and tablets don't have a SIM card slot and rely on Wi-Fi for their internet connection. If you need a connection when you're out and about you could search for some public Wi-Fi, or you could use your iPhone as a portable Wi-Fi hotspot and simply connect your tablet, laptop or another phone to your iPhone and let the other device share its internet connection. 

This is called tethering or internet sharing, and most mobile providers allow this now. (But if you don't see Personal Hotspot in your iPhone's settings, then speak to your carrier to find out why. It might be that your tariff doesn't support tethering.) Creating a Wi-Fi hotspot is much like having a mobile Wi-Fi router, but with no extra hardware required.

Once you've turned on your Personal Hotspot, any device with Wi-Fi can connect to the internet via your iPhone's data connection. Do note that the other device will behave as if it's on a home broadband connection and may download app updates, perform backups and other things that can quickly burn through your data allowance, so watch out for this when sharing your connection and keep an eye on your data usage.

How to enable a Wi-Fi hotspot on an iPhone

• On your iPhone open the Settings app and look for Personal Hotspot.

• Toggle the slider to turn it on if it's not enabled already

How to set up an iPhone Wi-Fi hotspot

• You may be prompted to turn on Bluetooth and Wi-Fi if they are off, but later versions of iOS don't warn you. In fact, in iOS 12, enabling Wi-Fi will disable the hotspot and disconnect any devices using it.

• Tap Wi-Fi Password and enter a password. This will be the be password you enter after tapping on the hotspot name in the list of Wi-Fi networks on the other device.

• 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.

Why is my Personal Hotspot not in the list of Wi-Fi networks?

If you can't see your phone's hotspot on the other device, check that Personal Hotspot is discoverable. To do this, open Control Centre by swiping down from the top of the screen (up from the bottom on older iPhones).

Long-press or 'deep' press on the top-left section to display the Personal Hotspot shortcut. It's likely it will be greyed out and say 'Off' or 'Not discoverable'. Simply tap it and wait until it turns green and the description changes to 'Dicoverable'. Now the hotspot should appear in the list of Wi-Fi networks on your other devices.

How to set up an iPhone Wi-Fi hotspot

If you have an Android phone, here's how to set up internet sharing on Android.