Apple currently sells four iPads, in four different sizes (defined by the diagonal measurement of their screen): the 7.9in iPad mini 4, the 9.7in iPad, the iPad Pro 10.5in and the iPad Pro 12.9in.

With size such a defining feature, the first thing to do when planning a purchase is to visit an Apple store or reputable retailer, get a feel for the products and see which size is right for you. Or, if this is not possible, cut out cardboard models in the correct dimensions and do your best to imagine what they'd be like to carry around and use.

But there's much more to it than that. Of the devices mentioned above, two are Pro models, which mean they are far more powerful and compatible with the Apple Pencil and Smart Keyboard accessories; the other two are less capable of running the most demanding apps (although you won't notice a difference on most day-to-day activities) but are correspondingly cheaper.

In our ranked roundup we examine the pros and cons of each current iPad model. For a more in-depth examination, however, take a look at our iPad buying guide 2017.

If and when you're ready to make a decision, you can buy the iPads direct from Apple, or check out our roundup of the best iPad deals. And each of the individual descriptions includes a buy now link.

1. Apple iPad

Apple iPad

It might seem odd that we're placing this at the top of the chart, given that we gave it only 3 stars in our review and said it "looks great but feels a bit cheap". But while it's not a perfect tablet by any means - and any prospective buyer should be warned of its shortcomings before making a decision - the superb price tag is low enough to make this the best iPad choice for most people.

The screen is unlaminated, which is a significant compromise, and means it flexes downwards very slightly when you press it: this is what produces that cheap-feeling sensation that sets it apart from other recent iPads. It's also thicker than any other current iPad - but at 7.5mm it's quite thin enough for most.

The A9 chip isn't as quick as the newer A10X Fusion, and on very processor-intensive apps and games, and particularly as time passes and more demanding apps are released, this will become apparent. But again, it's easily fast enough for general use and for running most apps on the store right now.

This tablet is a collection of compromises, and don't fool yourself into thinking it's the fastest tablet out there, or the thinnest, or equipped with the best feature set. But it's available at a great price, well-specced enough for most people, still a stunningly designed device and in our opinion the right choice for the average buyer.

2. Apple 10.5-inch iPad Pro

Apple 10.5-inch iPad Pro

If your budget goes a little higher - well, quite a lot higher, given the iPad 2017's terrific price tag - then you should plump for the iPad Pro 10.5in. It's about as good as tablets get.

Slender, mega-fast and extremely future-proof, not to mention equipped with an iPhone 7-standard camera and compatibility with the Apple Pencil and Smart Keyboard, this is a wholly feasible laptop replacement and, thanks to iOS 11's iPad-only features, a great work machine. The price is a bit punishing, however; although not as punishing as the 12.9in model we'll be discussing soon.

3. Apple iPad mini 4

Apple iPad mini 4

We used to love recommending Apple's iPad mini offerings, which tended to be its cheapest and most portable options. The second of those is still true, of course, but the first no longer is - partly because our top-rated iPad 9.7in (2017) is such good value, but also because Apple has removed the cheaper lower-storage options from the iPad mini 4.

This ultra-petite device remains a good option for those who want to slip their iPad into a jeans back pocket (just about) or the front pocket of a rucksack, and in terms of speed it won't let you down for surfing the web, watching videos, checking email and the like. The A8 chip is starting to show its age on graphically demanding games, however, and future-proofing is not great on this model: expect it to drop off the iOS update list a few years ahead of the other currently available iPads. (But that's still some way off: iOS 11 can be run by the mini 2 and mini 3.)

The mini 4 is clearly the best choice if portability is your priority, and if you're looking for a budget iPad but want a decent wedge of storage - a peculiar Venn diagram of users, that - then this is the cheapest 128GB tablet Apple sells. The screen feels nicer than the iPad 9.7in, too.

But we'd steer most people towards the iPad 9.7in if they're looking for value for money. And if you're looking for the best possible tablet the iPad Pro 10.5in is a much better option.

4. iPad Pro 12.9in (2017)

iPad Pro 12.9in (2017)

Bottom of the list, and least relevant to the average tablet buyer, the iPad Pro 12.9in is nevertheless a wonderful and ridiculously desirable device. It's the tech equivalent of those TV programmes about vast beautiful houses you could never afford.

The Pro 12.9in has the biggest screen here, of course, and for work, videos, graphically impressive games and pretty much everything an iPad can do that laptop-esque display is going to look fabulous. It also has the biggest battery, and despite the extra demands placed upon it this should ensure the longest battery life. But in every other respect the iPad Pro 10.5in does the same thing at a significantly lower price - and in a more portable body.

Thanks to iOS 11's multitasking features, workers on the go may feel this is worth the expense. And it's a great option for digital creatives and artists. But most of us will balk at that price tag - and may even consider a lower-end MacBook more manageable.