TOP 20 Tablets . . .

The original iPad may have launched way back in the mists of early 2010, but it's only now that there is a plethora of genuine iPad alternatives to choose from.

Nvidia's Tegra 2 CPU has been the driving force in a new generation of dual-core Android 3.0 tablets, while wildcard alternatives like the TouchPad and the PlayBook also sprung up running completely different operating systems.

We now stand on the brink of the next-next generation of tablets. Nvidia's 'Kal-El' Tegra 3 platform will imminently cross the streams with Google's 'Ice Cream Sandwich' Android 4.0 OS and give birth to a raft of exciting new products.

Apple is of course putting the finishing touches to the iPad 3, and there's also a whole raft of other innovative tablets on the way with glasses-free 3D screens and all sorts of features you probably haven't even heard of yet.

So let's take a look at the best of the bunch as they currently stand. These are the top 20 best tablet PC iPad alternatives – there's one for you in there somewhere!

UK release date: Autumn/Winter 2011
Specs: Android 3.2, Nvidia Tegra 2 dual-core CPU, 10.1-inch capacitive display at 1280x800, slide-out keyboard, micoSD, HDMI-out, rear-facing camera, front-facing camera

What we think: While the form factor might not suit those going for an iPad-a-like Android option, the Slider is still a gorgeous tablet. With its slide-out QWERTY keyboard, it offers the perfect balance between portability and functionality. It's also got an absolutely gorgeous screen, and offers the best Android 3.2 touch experience of any tablet out there.

UK release date: Autumn 2011
Specs: Android 3.1, 1GHz dual core Nvidia Tegra 2 CPU, 1GB RAM, 16GB storage, 8.9-inch capacitive screen at 1280x800 (WXGA), Wi-Fi only, 447g.

What we think: The Samsung Galaxy Tab 8.9 is almost indistinguishable from its 10.1-inch big brother. To that end, it's a fantastic tablet which is both significantly lighter and thinner than the iPad 2. It's ideal for anyone who thinks 10.1 inches is just slightly too big for a tablet, but also finds 7-inch options a tad too small. A great screen, and premium features across the board make it a superb option.

UK release date: Out now
Specs: Android 3.2, Nvidia Tegra 2 dual-core CPU, 10.1-inch capacitive display at 1280x800, full-size keyboard dock, card reader, HDMI-out, rear-facing camera, front-facing camera

What we think: Asus is keeping all its bases covered by offering a variety of different tablet options, and waiting to see what people buy. The Eee Pad Transformer comes with a keyboard dock and the whole package costs just £429 - a veritable bargain. Asus is certainly flying under the radar when it comes to marketing its new tablets, but you should associate the name with words like 'quality' and 'user experience'. This is a fantastic product.

UK release date: Out now
Specs: Android 3.0, 1GHz dual core CPU, 1GB RAM, 16GB/32GB storage, 10.1-inch capacitive screen at 1280x800 (WXGA), 3MP rear-facing camera, 2MP front-facing camera, 3G, 599g.

What we think: As an out-and-out tablet, the Galaxy Tab 10.1 is brilliant. It matches the performance of the other Honeycomb Tegra 2-based tablets while beating the pants off them in the portability stakes. This tablet is the lightest and thinnest 10-inch tablet in the world - and yep that includes the iPad 2. So unless that keyboard dock above is a serious draw for you, this is currently the one to watch.

UK release date: Out now
Specs: Android 3.2, 1GHz dual core CPU, 1GB RAM, 16GB/32GB storage, 10.1-inch capacitive screen at 1280x800 (WXGA), 3MP rear-facing camera, 2MP front-facing camera, 598g.

What we think: We love the Sony Tablet S and its wedge-shaped design. It really makes it stand out from the crowd. The responsive touchscreen and unique shape combine to make this tablet extremely usable, and a joy to type on. If you're choosing an Android tablet you won't be disappointed, but if it's a shoot out between the Sony Tablet S and the iPad 2, unless you're a hardened Sony fan, then your money is still better spent with Apple.

UK release date: Out now
Specs: Android 3.0, Nvidia Tegra 2 dual-core CPU, 1GB RAM, 32GB Flash storage, 10.1-inch capacitive LCD at 1280x800, proximity sensor, ambient light sensor, barometer, gyroscope, 5MP rear-facing camera, 2MP front-facing camera, 3G, 730g.

What we think: The Motorola Xoom is one of the second-generation Android tablets that the tech world got very excited about when it came out. Packing Nvidia's super-powerful Tegra 2 chip and running the tablet-friendly Android 3.0 OS, the Xoom was the first genuine iPad challenger. Ultimately though, it failed to attract buyers, which is why you've probably never seen one. These days, while the Xoom is still a decent, premium and well-built tablet, there are simply better options available. Stay tuned for the Xoom 2, coming very soon!

UK release date: Out now
Specs: BlackBerry Tablet OS (QNX), 1GHz Cortex A9 dual core CPU, 1GB RAM, 7-inch capacitive LCD at 1024x600, 3MP front-facing camera, 5MP rear-facing camera, 400g.

What we think: The BlackBerry PlayBook is designed to be mobile and business-friendly. That means, at 130x194mm, the device is small enough to hold with one hand, slip in a laptop bag side pouch, and even carry around all day to meetings. The problem's start, though, with the lack of an email app, the dependence on owning a BlackBerry smartphone and a terminal lack of apps. The Playbook is powerful and has brilliant multitasking capabilities, but for now it's one to watch rather than one to buy.

UK release date: Out now
Specs: Android 3.0, 1GHz Tegra 2 CPU, 1GB RAM, 32GB storage, 8.9-inch capacitive screen at 1024x768, 2x 5MP rear-facing cameras for 3D capture, 2MP front-facing camera, phone-friendly 3G, 630g.

What we think: The Optimus Pad is a super-looking tablet and has the USP of having dual 5MP rear-firing cameras for 3D image capture. Add to that dual-core Tegra 2 CPU, a decent screen and Android 3.0 and you've got an exciting tablet on your hands. But pricing could be this tablet's Achilles heel – it's pricey. And frankly, 3D image capture without a 3D display = a product before its time. In 2012 we expect to see the LG Optimus Pad 3D, but until then, this probably isn't for you.

UK release date: Out now
Specs: Android 3.2, 1GHz dual core CPU, 1GB RAM, 8GB/16GB/32GB storage, 10.1-inch capacitive screen at 1280x800 (WXGA), 5MP rear-facing camera, 2MP front-facing camera, 725g.

What we think: The Toshiba AT100 (known as Toshiba Thrive outside Europe) is a good choice for those who like the idea of full-size HDMI and USB ports. For a specific use, including customisations and future upgrades, the Toshiba AT100 offers some extra flexibility.Yet, the hefty size and weight (plus the passable screen quality) is the main reason we prefer other recent tablets.

UK release date: Out now
Specs: Android 2.3, 1.5GHz single-core Snapdragon, 1GB RAM, 32GB memory, 7-inch capacitive LCD at 1024x600, 5MP camera, 3MP front-facing camera, phone-call-friendly 3G, 415g.

What we think: HTC has decided to release its first tablet running on Android Gingerbread (2.3), which will upset some purists that only believe these tablets should run on Honeycomb. However, it does come with a new version of HTC Sense with dual-pane windows which works well with videos and email. As a single-core device in a dual-core world, though, the Flyer just isn't good enough. And the chunky form factor and lack of sparkling features are a real let-down.

UK release date: Out now
Specs: Android 3.2, Dual-core CPU, 10.1-inch capacitive display at 1280x800, HDMI-out, rear-facing camera, front-facing camera, multiple storage options including 250GB HDD.

What we think:If you're in the market for a capable tablet, but have a limited budget, then this is one of the best options outside of price cuts that you can get.The potential problem is we're about to be bombarded by cut-price tablets, and much better units can be had for this kind of cash - tablets with more memory, built from better materials and generally put together with more love.

UK release date: Out now
Specs: Android 2.2, Qualcomm MSM 7227 600MHz CPU, 512MB RAM, 512MB storage, 7-inch capacitive LCD at 800x480, 3MP rear-facing camera, VGA front-facing camera, phone call-friendly 3G, 375g.

What we think: Not technically built by Viewsonic, this tablet is also available under various different titles. Essentially it's a Chinese-built OEM device, but you'd be wrong if you think that means it's not very good. It is. It's responsive, it's a nice size and it's usable. The problem is that at launch it should have cost £200, not £400. And even though it can now be found for around £180, the ship has sailed!

UK release date: Out now
Specs: Intel Atom N450 1.66GHz CPU, 2GB RAM, 23GB/64GB, 11.6-inch capacitive LCD at 1366x768, 1.3MP front-facing camera, 950g.

What we think: While the list is dominated by Android tablets, let's not forget poor old Windows 7. It's in no way a touch-friendly operating system, but that doesn't mean there isn't some decent hardware out there doing its best. The ExoPC Slate is the best Windows tablets at present, and so if you MUST have Windows on your tablet, this is currently the one to get.

UK release date: Discontinued
Specs: webOS 3.0, 1.2GHz dual-core Snapdragon CPU, 1GB RAM, 16GB, 32GB storage, 9.7-inch capacitive screen at 1024x768, 1.3MP front-facing camera, 740g.

What we think: The HP TouchPad is less polished than the iPad, with a smaller range of impressive third-party apps. Yes, it's got features that the iPad lacks, but so do the Android tablets, and they have a bigger app selection, too. The interface appears more polished than many Android tablets, but in operation that doesn't really stand up. It's also lagging behind in many hardware features, such as HDMI output. And it's also not very tricky to get hold of, as HP killed it just a couple of months after it launched. If you can pick one up cheap though, it could be a good budget option.

UK release date: Out now
Specs: Android 3.0, Nvidia Tegra 2 dual-core CPU, 1GB RAM, 10.1 capacitive screen, 5MP rear-facing camera, 3G.

What we think: The A500 was ultimately a disappointment. It was relatively competitive on price, but it simply did not offer the same good looks as the likes of the iPad or Galaxy Tab. It will forever be known as an also-ran, but you can be sure that Acer will be back for more next year. If you can find this model at a crazy cheap price, it might be worth a splash. But otherwise, you should opt for one of the tablets higher up in this list.

UK release date: Out now
Specs: Android 2.2, 1GHz Cortex A8 CPU, 512MB RAM, 16GB/32GB, 7-inch capacitive LCD at 1024x600, 3.2MP rear-facing camera, 1.3MP front-facing camera, phone-call-friendly 3G, 380g.

What we think: While the Galaxy Tab promised the world, it didn't quite deliver the tablet experience we were hoping for. As the first big-name tablet to take on the iPad, it failed to live up to its billing. That said, user response has been positive, and despite the ageing features, this first-generation Android 2.3 tablet can now be picked up for under £200 if you look hard enough.

UK release date: Out now
Specs: Android 3.0, Nvidia Tegra 2 dual-core CPU, 7-inch capacitive screen at 1024x600, 5MP rear-facing camera, 2MP front-facing camera, 3G.

What we think: The A100 is the little brother to the Acer Iconia Tab A500, and it's not a bad option all-told. It's hardly a great looker though, and ultimately fails to make a case for itself among better and more aggressively priced competitors.

UK release date: Winter 2011
Specs: TBC...

What we think: We don't know much about the Asus Eee Pad MeMo yet. What we do know is that there are four models in the Asus Eee Pad range, and the MeMo is the one yet to see even a hint of a release. We do know that Asus is taking its time with these Eee Pads, so we can be fairly confident that when it does finally go on sale, it'll be good. And the latest news suggests it may have a glasses-free 3D screen.

UK release date: Early 2012?
Specs: Heavily modified Android 2.3, 512MB RAM, 1GHz Texus Instruments OMAP 4 4430 CPU, 7-inch capacitive screen 1024x600, microUSB port, Amazon Sevices bundled, 8GB storage

What we think: After months of speculation, the Amazon Kindle Fire has been officially announced at an event in New York, marking the first time the company has entered the tablet market proper. The successor to the Amazon Kindle is a 7-inch device that comes with Android, albeit a version that has been heavily altered by Amazon to make the best use of the company's e-shopping spine.The screen is an IPS display that's made from Gorilla Glass, it houses a dual-core processor, and weighs in at 14.6 ounces. There is a tablet-optimised shopping app on board - this is said to comprise simplified and streamlined pages, so it is easier to buy stuff on than the actual Amazon website.