Hardware is just one part of the equation when buying a tablet, with its operating system being potentially the deciding factor when making your choice. With this in mind, we take a look at the various operating systems used by tablets to see what each has to offer.

Tablets are defined by their hardware design. They are flat, slate-style computers, with no physical keyboard. They come with a range of different screen sizes, and a variety of different internal specifications, but overall they all share a similar look. For the consumer, the factor that differentiates tablets the most is probably the operating system. Many people choose a tablet because it is an iPad running Apple’s iOS, or decide to select a tablet from those that run Android, or specifically want to opt for the BlackBerry PlayBook because of its operating system.

So what is it about each operating system that draws people in? What are the pros and cons that each operating system offers, and what are the specific factors that make one more alluring than any other? Let’s take a look.

Google Android explained

Android takes the prize for being found on more tablets aimed at the consumer or leisure user than any other operating system, and it does so by a country mile. The first Android tablets that appeared were running version 2.x, such as the original 7in Samsung Galaxy Tab and the HTC Flyer.

However, that version of Android wasn’t optimised for use on tablets, and most major manufacturers decided to wait until Android 3, also known as Honeycomb, to come on to the scene in the early part of 2011. Since then things have move quickly, with tablets running Honeycomb appearing thick and fast so that now you’ve plenty to choose between. Android 3.x (so far, we’ve seen versions 3.0, 3.1 and 3.2 on different tablets), takes an approach based around multiple home screens, which can be customised with widgets and shortcuts, in a similar way to its sibling smartphone software. It is highly finger-friendly, and widgets can contain live data such as calendar content or social media updates.

Just as in smartphones, Android on tablets uses your Gmail address to pick up email, and comes with Google Maps and YouTube as standard as well as a range of other applications including a web browser, calendar (with Google Calendar sync), messaging application and music player. It also includes GPS support for mobile navigation and location-based services.

You can add more applications via the on-device Android Market, though of the many thousands of apps that exist for Android remarkably few are optimised for use on tablets, instead they simply retain their original design that is suited to smaller smartphone screens. Still, the number of tablet-native applications is growing steadily.

Future prospects look bright for Android. The next incarnation, known as Ice Cream Sandwich, will launch soon and combines the smartphone and tablet operating systems. Ice Cream Sandwich is a clear indication that Google sees tablets as just an important a part of its future as are smartphones.

iOS for iPad explained

iOS is Apple’s mobile operating system. Launched on the iPhone in 2007, it has since made its way to the iPod touch and on to Apple’s tablet, the iPad. iOS is not available to third-party hardware developers, with the only products carrying it being made by Apple.

As far as tablets go, there is just the one iPad in Apple’s current stable, the iPad 2, a thinner, lighter update of the original iPad. The iPad 2 is available in versions with or without 3G support and with either 16GB, 32GB or 64GB of internal memory as well as with either a black or white chassis. But for all that variety, the iPad 2 is the iPad 2 is the iPad 2, with its distinctive look and feel, sleek hardware design, and clean lines.

iOS itself is arguably the most finger-friendly of tablet operating systems, its overall user interface design translates well from the 3.5in screen of the iPhone and iPod touch to the 9.7in screen of the iPad 2. It is arguable that Apple more than any other company has understood what it means to make a touch-intuitive, good-looking and attractive operating system for tablets, with its large shortcut icons that feature rounded corners being a defining characteristic. When people are trying to define the world ‘cool’, Apple’s iPad often pops up as a prime example.

iOS has built-in support for mobile email, mapping, GPS, music playback and more, and supports Google synchronisation for email, calendar and contacts. Like Android, iOS is supported by a rich and vibrant applications market, though again like Android many of the thousands of applications in the market are not optimised for the large tablet-sized screen. You will, though, find plenty that are, and those that are not can be automatically resized, so that they don’t look too lost on the iPad’s large screen.

iOS is one step ahead of Android in already being unified across mobile devices of different sizes, and Apple is clearly committed to developing the platform as the iPhone, iPod an iPad are all key elements of its hardware base. However, one big drawback of iOS is that, unlike the other tablet operating systems, it does not support Flash, so that it’s not possible to view video embedded into some web sites.

BlackBerry Tablet OS explained

Research in Motion (RIM) is known for its BlackBerry range of smartphones. Like Apple, RIM does not license its operating system to third-party hardware manufacturers (though it did make a brief foray in that direction a few years ago). In 2011, RIM took its first steps into the tablet arena with a single device, the PlayBook.

The PlayBook is a small format tablet with a 7in screen. It features a top-of-the-range dual-core processor, two cameras, and Wi-Fi but no built-in 3G support. The PlayBook runs a new operating system called BlackBerry Tablet OS, one of whose star features is great support for multi-tasking (running more than one application at the same time).

The PlayBook is designed to fit into an existing technology portfolio that includes other BlackBerry devices, such as its range of smartphones. It is compatible with BlackBerry Enterprise Server, for example, the corporate software that allows BlackBerry users to synchronise their email, contacts and calendar while on the move.

One of the key features of the BlackBerry PlayBook is its ability to connect to a BlackBerry smartphone via an application called BlackBerry Bridge. This connection is made via Bluetooth, and once in place you can access content from the BlackBerry smartphone, such as email and view and edit it on the larger screen of the PlayBook. The PlayBook can also use the BlackBerry smartphone for 3G connectivity.

This concept is attractive to companies as it means the PlayBook doesn’t have to be brought into their security systems, but it also means that without a tethered BlackBerry phone the PlayBook’s features are limited. Email, for example, has to be done as webmail. Tethering to a BlackBerry smartphone requires a live Bluetooth connection and, as our experience with the PlayBook left us with some concerns about battery life, we weren’t sure about the possibility of maintaining live Bluetooth connections for long periods.

A range of applications comes as part of the operating system. This includes a music player, Bing Maps, PDF reader, document viewing and editing and a good web browser. There is also an application market on the PlayBook, but at the moment it isn’t particularly well filled with third-party applications and does not measure up well against either the Android Market or iOS app store.

The PlayBook is a relatively new venture for RIM and the jury is out on whether it is going to be a successful one or not. In its current guise, the PlayBook is much better suited to the corporate sector than to consumers, which is odd, really, given the device’s name. We wait with interest to see where RIM decides to take the PlayBook and the BlackBerry Tablet OS.

Windows for tablet explained

Windows needs no introduction. It’s the operating system used in the majority of desktop and laptop computers sold around the world and even if it is not in the computer you currently consider to be your main one, you are more than likely to have used it at some time. An argument can be made for Windows playing a very important part in the history of tablets. Microsoft made a touch-supporting version of its Windows operating system in 2002, which was released with the Windows XP Tablet Edition.

Today, Windows tablets are sold in significant numbers, even though Google’s Android operating system is available on a wider range of models. It should, however, be noted that sales of Windows tablets are almost entirely from what are known as ‘vertical markets’, such as health care. Its tablet users are mostly professionals who are utilising their devices in a working environment.

Some tablet manufacturers have started producing more consumer-friendly Windows 7-based tablets. The Acer Iconia Tab W500 combines Windows with Android, the latter sitting on top of Windows when you run it. Fujitsu has added a finger-friendly overlay on to Windows with its Fujitsu Stylistic Q550.

However, Windows is not currently in the running as far as consumer-focused tablets are concerned. Windows does not do well in consumer-focused tablets because it is far from finger-friendly. Its small icons, drop-down menus, and application launching system were designed for use with a cursor and mouse, and while they can be used with a stylus, they are too small and fiddly for easy access with a fingertip.

This must be an irritation to Microsoft, whose Windows operating system has great support for third-party applications, a vast library of paid for and free software, support for mobile connectivity in the form of Wi-Fi, Bluetooth and 3G, and a huge, established user base that is already familiar with the operating system and how it works.

Microsoft hopes to overcome many of the problems of finger-friendly use with Windows 8, which has been specifically designed to sport a tiled front end that looks rather like the one you can see on its current Windows Phone smartphone OS. Microsoft also plans to open its own app store, which will let you buy apps that are specially designed for touch-friendly use as well as more traditional-looking Windows software.

You might not choose a Windows-based tablet if you are shopping around today, but we think it is worth keeping an eye on Windows 8 as one to watch for the future.