What is 4G?

4G is the fourth generation of mobile phone technology, following 2G and 3G.

2G technology was suitable for making calls and sending text messages, while 3G makes it possible to access the internet more effectively through your mobile phone.

4G makes it easier to access the internet on your mobile, tablet or laptop. It's ideal for services that demand more capacity, like video streaming, mapping and social networking sites.

For the typical user, download speeds of initial 4G networks could be around 5-7 times those for existing 3G networks.

This means a music album taking 20 minutes to download on a 3G phone and just over 3 minutes on 4G. This is based on existing 3G speeds being 1Mbit/s on average and 4G speed being 6Mbit/s (average of 5 and 7 times faster).

Buying a 4G phone

4G mobile phones are built to work on specific types of frequencies.

Much like some cars are built to run on different types of fuels, if you try and put diesel into a car that’s designed for petrol, it won’t work. Equally, a 4G phone will only work on frequencies it was designed to use.

Mobile operators may use different frequencies to deliver 4G services. Therefore, if you sign up to a 4G contract with one provider and then decide to switch to a SIM only contract with another provider, you may lose the 4G functionality of your phone.

If your provider does not already offer 4G; but you are thinking of buying a new handset in preparation for when it does, it is slightly more complicated than simply choosing a ‘4G ready’ phone. This is because the phone might not be compatible with the frequencies that your provider will end up using to deliver 4G.

One way of ‘future proofing’ your purchase could be to choose a handset that runs 4G on several different frequencies.

Think of this as the 4G equivalent of buying an old 2G phone with a ‘tri-band’ setting, which supports most of the 2G frequency bands used around the world. Or to use the analogy of the car, you would be buying a hybrid, which runs both on electricity and petrol.