A smartphone's small screen isn't as good as a tablet's for browsing the web or streaming videos from Netflix, though. The good news is that it's possible to use your smartphone as a portable Wi-Fi hotspot, and share its data connection with your Wi-Fi-only tablet.
This setup is called tethering or internet sharing, and many smartphones provide this feature, including iPhones, BlackBerrys, Windows Phones and, of course, Android handsets.
What does tethering mean for Android, iPhone, BlackBerry and Windows Phones?
Tethering is when you turn you smartphone into a mobile Wi-Fi hotspot and share your phones 3G/4G data connection. Once you've turned tethering on, any device with a wireless connection can connect to the internet via your smartphone's connection.
'Tethering' means the same thing no matter what smartphone OS you are using. The only difference is how you enable it on each platform.
Does my smartphone work as a Wi-Fi hotspot?
Not all smartphones support tethering, but most popular models do, including the iPhone, Samsung Galaxy S3, Nokia Lumia 920 and BlackBerry Z10. You don't have to use Wi-Fi to share your phone's internet connection: some allow you to connect a laptop (possibly even a tablet) via a USB cable. Alternatively, you might be able to use Bluetooth.
Regardless of the connection method, it's important to check whether your mobile tariff allows tethering before using your smartphone 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, for example).
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.
If you happen to have a giffgaff SIM in your iPhone, you're out of luck as giffgaff isn't recognised by Apple as an official carrier. You'd need to jailbreak your iPhone to get around this.
I'm not allowed to tether on my tariff. What are the alternatives?
First, and most obviously, you could switch to a different operator or tariff (or request a bolt-on to your current tariff) that allows you to use your smartphone as a Wi-Fi hotspot. That might mean paying more each month, but it's likely to work out cheaper than the alternatives.
If you haven't already bought a tablet, you might consider buying one with 3G or 4G support. You'd then have to get a data-only SIM card for it, and either pay monthly or pay as you go for this separate tariff.
Another option is to invest in a portable Wi-Fi hotspot, also known as MiFi. These battery powered devices are essentially wireless routers into which you pop a SIM card, just as you would a 3G or 4G tablet. They cost from around £50 or might come as part of a package with a data SIM.
If you want a device that will work in other countries as well as the UK, you'd do well to investigate Globalgig - reviewed.
How does tethering work?
Put simply, the process involves enabling the hotspot option on your phone, configuring wireless security with a password to prevent other people piggybacking on your connection, then connecting your tablet to the wireless network just as you would with any hotspot.
You'll have to enter the password the first time you connect, but on subsequent occasions, your tablet should connect automatically. It's the same process if you have a MiFi dongle.
Pitfalls to watch out for
One of the potential problems with using your phone as a portable Wi-Fi hotspot is that your tablet will think it's connected to a fixed broadband line, rather than a mobile connection.
This means it could gobble up your limited monthly data allowance very quickly. Whereas your smartphone will avoid downloading app updates and any other large data files on 3G, your tablet could assume that's perfectly fine.
For this reason, either disable automatic updates or downloads. Or keep a close eye on how much data is being used by looking in your phone's settings or via a dedicated app.
On your smartphone, disable the hotspot running when you're not using it as this will prolong battery life.
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