Sony Xperia Z White (4G-ready) - Specifications

The operating system you use (like iOS, Android™ and Windows Phone) will depend on your phone.

The size of your phone's internal memory will determine how many pictures, videos and music tracks you can store on your phone. Some phones also come with a memory card slot so you can increase the memory.

Screen sizes are measured diagonally. The bigger the screen, the better the viewing will be when you're browsing the web or watching videos.

A 3G network allows high-speed web access and advanced browsing.

This is where in the world your phone can be used. Some phones can be used worldwide, while others are restricted to the UK or Europe.

If your phone's Wi-Fi enabled, you can connect wirelessly to the internet when you're in a Wi-Fi hotspot (including airports, restaurants and train stations).

GPS allows you to pin-point your location using satellites. So you can use SatNav applications on your phone, or even find somewhere to eat when you're out and about.

If your phone's got an LED flash, you'll be able to take better photos in dark conditions. And with a dual-LED flash you'll get an even clearer image.

The quality of the videos you record on your phone depends on the resolution and frames per second. VGA is lower than 720p (HD) and 1080p (full HD).

The operating system of your phone will come with its own application store - where you can download apps and games to your phone (some of them for free).

Transfer music and pictures from your PC or Mac straight to your phone.

Instant messaging (or IM) is like real-time texting. Some phones come with pre-installed instant messaging applications like MSN and Facebook Chat.

Make a phone call without having to search through your phonebook. Voice-activated dialling means you can simply say the name of the person you want to call and the phone will dial their number automatically (you'll need to set this up first).

Adobe Flash Player lets you view videos and animations on web pages as they were meant to be.

Content Control stops customers under the age of 18 from accessing inappropriate content. This can be removed.