Tablet reviews: Features explained
The touchscreen is what you interact with to control the tablet. Similar to using a mouse and cursor on a computer, you touch the screen and swipe your finger to make selections, open up programs, move up, down and across pages and zoom in and out. You also use the on-screen keyboard to input text - so a screen that reacts accurately and instantly is essential.
There's a big difference between a good touchscreen and a bad one. The best feel very responsive and accurate, the worst feel very slow to react and are frustrating to use.
Read our Which? reviews of the best tablets to find out which tablets get five-stars for the quality of their touchscreens.
Just like computers and laptops, tablets are available with a variety of different memory options. Cheaper tablets tend to have 8, 16 or 32GB of memory built-in, while more expensive tablets offer 64 or even 128GB of space.
The memory is used to store apps and media content - such as music, video and photos. If you plan to use your tablet for heavy-weight apps such as games, you'll want a larger memory. As a rough guide, a two hour HD film uses about 3.6GB, 12 albums of music about 1GB, while games can range from 20MB to 500MB (0.5GB) and beyond.
The operating system and pre-installed apps will already take-up some of the space. Our tests measure just how much memory is really available, once the OS has been taken into account so you know how much is free for you to use.
If you find you run out of space you can use cloud storage to store content. Read our guide to cloud storage for more information.
Alternatively, on most tablets, there is a memory card slot - useful for expanding the memory of your device. It's worth noting that Apple iPads do not come with a memory card slot.
The operating system, or OS, is the software platform which runs all the apps and functions on your tablet.
Currently there are three types of operating system - the Apple iOS, the Android platform, and the two types of Microsoft Windows operating system.
Apple iOS - Unlike other tablet hardware manufacturers, Apple has its own operating system designed specifically for mobile devices such as tablets and smartphones.
It's simple to use, and even if you haven't used a tablet before you'll be able to navigate the menu without any problems.
You can download apps from the Apple app store - which has the largest selection of apps available.
Android OS - Aside from Apple, most tablet manufacturers, such as Samsung, Google and Amazon, use the Android operating system. Android has a confectionery theme to help name the operating system. The current version is called Lollipop, with previous versions named KitKat, Ice Cream Sandwich and Honeycomb.
Manufacturers are able to tweak the Android system to suit their needs. For example, the Amazon tablets have restricted access to the Google Playstore, in order to tie you to the Amazon Kindle ebook system.
Windows - Released at the end of 2012, Windows RT is the first Windows OS built specifically for mobile devices. The Microsoft Surface RT is the first tablet to run on this system.
It is also possible to run the full Windows 8 operating system on a tablet. This gives you full functionality - meaning you can use your tablet to do the same tasks as you'd use your laptop for. However, the Windows 8 OS takes up more memory and guzzles more energy than the RT version. The Microsoft Surface Pro runs the full version of Windows 8.
The Windows 8 and RT homescreens look different to the traditional Windows layout. A series of brightly coloured tiles are designed for you to swipe or tap with your finger, and are displayed on the main menu, where there isn't a Start button.
This takes a little while to get used to - but does suit touchscreen devices well.
The Windows apps store isn't as well populated as the Android or Apple stores - but this is likely to change over time.
For more info read our head to head on Apple, Android and Windows operating systems.
Wi-fi, 3G and 4G
Tablets are great for browsing the web, but to do that you will have to get online. You can do this via wi-fi at home, if you have a wireless router set up. Outside the home, many cafés, pubs, restaurants and other public places have wi-fi networks that you can use.
However, if you want to regularly use your tablet on the move it might be worth opting for the 3G or 4G version of the tablet.
3G tablets work in the same way as the internet on your smartphone - connecting to the internet via mobile broadband. You'll need a dataplan with a mobile provider - this will typically cost about £10 per month.
Included in your monthly payment is an online allowance in addition to your wi-fi use, which allows you to use the web and download what you want up to a limit.
Deals vary, but a 1GB monthly limit is quite typical. 1GB is roughly equivalent to 10 hours of web-browsing a week, 50 emails sent and received each week, four software updates a month, 10 photos uploaded or downloaded each month, 5 short video clips each month, and 5 music tracks downloaded each month.
If your tablet doesn't have built-in 3G, you can sometimes tether your tablet to your mobile phone, sharing the phone's 3G connection with the tablet.
To do this, you connect the two devices, usually via wi-fi. Some mobile phone networks charge for this service, with only some phones being supported in certain cases. Check with your network provider for details.
Short for application, an app is a program that can perform specific tasks. It could be a game, a piece of office software, a news or weather program, a tool to help you find train departure and arrival times, catch up on TV programmes you've missed, or check in on your friends through Facebook.