Which iPad should you buy? It's a tricky question that's growing even more difficult now that Apple's iPad range is expanding. Apple currently offers the iPad Air 1, iPad Air 2, iPad mini 2 and iPad mini 4, as well as the upcoming iPad Pro. To help you make the decision about which iPad you need, we've got a complete guide with iPad buying advice that'll help you choose the iPad that's best for you.

Which is the best iPad: How to choose which iPad is best for you

If you head over to Apple's website now with the view to buying an iPad, you might be surprised to find that you're faced with five different models, and each of those comes with lots of options including storage space and the choice between cellular or WiFi-only.

The key is to figure out your priorities. Is price the most important thing you want to consider? Or maybe it's portability? And what do you plan on using your iPad for? Do those tasks require more power (maybe it's graphics-intense games or productivity for business purposes)?

Once you've started figuring out the answers to those questions, continue reading and it should soon become clear which iPad is right for you.

Which is the best iPad: iPad Pro

The most expensive tablet available from Apple is the iPad Pro, but it's actually not out yet and isn't coming until November, when we expect it'll be in high demand. We don't know the official price of the iPad Pro yet but you can expect it to be around the £700 mark, as it's officially $799 in the US. That's for the 32GB model, but there's also a 128GB model for $949 and a 128GB + Cellular model available for $1079.

The iPad Pro has the biggest screen at 12.9in, and is designed to be a rival to the likes of the Microsoft Surface Pro 4 with an optional keyboard and stylus that brings it closer to a laptop for more serious users. It boasts a powerful new A9X chip that's designed to be 2.5x faster than the A7 chip found in the iPad Air 2, with 5x faster graphics.

It'll be available in Silver, Space Grey or Gold.

We expect the iPad Pro to be popular among business users and creatives. If that sounds like you, you can find out more about the iPad Pro by following the links below.

iPad Pro vs iPad Air 2 comparison
iPad Pro vs Laptop: Can the iPad Pro replace a laptop?iPad Pro vs Surface Pro 3 comparison

Which is the best iPad: iPad Air 2

Second in the line-up is the iPad Air 2, which comes in at a cheaper starting price of £399 but that's for a 16GB model, which we'd advise avoiding if your budget can stretch to £479 for the 64GB model (there's no 32GB model of Apple's iPad Air 2). 16GB runs out fast so you'd be future-proofing the tablet by opting for the 64GB, as there's no microSD card slot available for adding storage. There's also a 128GB model for £559 and they're each upgradeable to add cellular connectivity for an extra £100. If £399 is top of your budget, we'd recommend considering opting for either the 32GB model of the iPad Air 1 for £359 or the 64GB model of the iPad mini 4 for £399, both of which we talk more about below.

The iPad Air 2 is brilliantly thin and light, and it's powerful too with an A8X chip that can't quite live up to the power of the iPad Pro, but is 1.4x faster than the iPad Air's A7 chip and 2.5x faster when it comes to graphics.

The iPad Air 2's 9.7in screen is ideal for watching movies and playing games, and works well if you plan on using iOS 9's Split Screen feature to run two apps simultaneously side-by-side, but it does make it less portable than the iPad mini 4 and iPad mini 2's 7.9in.

It's available in Silver, Space Grey or Gold colour options.

Read more in our iPad Air 2 review.

The iPad Air 2 isn't just available from Apple, either. You'll find it in reseller stores including Currys, Co-op, John Lewis and Amazon, and you'll often find that there are speciall offers available that you wouldn't find from Apple.

Which is the best iPad: iPad Air 1

If you're keen on that 9.7in screen but want to spend a bit less money, the 16GB model of the now two-year-old original iPad Air is available for £319, and the 32GB is £359. There's no 64GB or 128GB model available, but you can choose to add cellular for £100.

That screen has the same 2048x1536 resolution with a pixel density of 264ppi, but the iPad Air 1 is thicker at 7.5mm and heavier at 469g (but actually we think that's still wonderfully thin and light so it won't matter to everyone). It also has a slower processor, but unless you intend to play graphics-heavy games you probably won't notice. It does mean that you miss out on the Split Screen feature, though.

The camera is also less impressive, at 5MP compared with 8MP for the iPad Air 2, but we don't know many people who enjoy taking photos with their tablet so that's probably not a deal breaker either.

It's only available in Silver or Space Grey so you won't be able to get a Gold iPad Air, and it also lacks the Touch ID fingerprint sensor that you'll find in the iPad Air 2 and iPad Pro, as well as the iPad mini 4.

Read more in our iPad Air 1 review.

In addition to Apple, you can also buy the iPad Air 1 from resellers such as Amazon, Currys, Tesco, and Argos, often at a reduced price.

Which is the best iPad: iPad mini 4

The iPad mini 4 is one of our favourite iPads right now, because it's super-portable, fast and stylish. It's essentially a miniature version of the iPad Air 2, with most of the same specs and features. The obvious difference, of course, is that it has a 7.9in screen instead of 9.7in, but that also means it's lighter at just 299g and can fit into small bags and in some cases even pockets.

It does have a slightly less powerful processor than the iPad Air 2, though, with an A8 instead of an A8X, but you'll still be able to use the Split Screen mode and most apps should run smoothly without any lag.

It's available in all three colour options: Silver, Space Grey and Gold. And just like the iPad Air 2, there's 16GB, 64GB, 128GB models for £319, £399 and £479 respectively, and we'd recommend the 64GB model if your budget can stretch to it.

Find out more in our iPad mini 4 review.

The iPad mini 4 is also available from the likes of John Lewis, eBuyer and Amazon, too, so it's well worth checking whether you can save money there or get yourself a special deal.

Which is the best iPad: iPad mini 2

The final iPad on the list is the two-year-old iPad mini 2, which has the same 7.9in screen with the same resolution, but is significantly less powerful with an A7 chip and has a 5Mp camera, no Touch ID fingerprint sensor, is thicker at 7.5mm and weighs more at 331g.

Of course, that does make it much cheaper, and you can get the 16GB model of the iPad mini 2 for just £219. We'd recommend opting for the 32GB £259 model if you can, though. And as with the other iPads listed, you can upgrade to WiFi + Cellular, but that'll add £100 to the price.

Find out more in our iPad mini 2 review.

You'll also find the iPad mini 2 from third party resellers, including Amazon which is currently selling it for just £204.

Which is the best iPad: WiFi-only or WiFi + Cellular?

If you're struggling to decide whether to opt for the WiFi-only model or to cough up the £100 for cellular connectivity, we can help. If you want to use Facebook, email, YouTube or any other web-based tool in the car or on the train, you're going to want a Cellular version, which gives you 3G/4G connectivity.

If you do opt for Cellular, you'll need to get yourself a data-only SIM, and you'll be required to pay for data monthly.

Stick with a WiFi-only iPad if you'll mainly use your tablet at home on your wireless network or when connected to your office WiFi.

If you're after an internet connection when abroad, it will typically be cheaper to find a WiFi hotspot in a café or hotel than roaming on a UK SIM. However, buying a pre-paid foreign SIM from a supplier such as Dataroam can also work out fairly cheap.

One important factor to bear in mind is that WiFi-only iPads do not have a GPS receiver, so can only approximate your location using WiFi hotspots. This means that if you want to use your iPad for directions you will need to buy a cellular model.

Which is the best iPad: How much storage do I need?

It's tempting to opt for the base 16GB version, since it's much cheaper than the other models. If you know that you won't want to store your music and video collections on your iPad, 16GB should be enough. However, you might be surprised how quickly apps eat up the storage space. With so many free apps, it's sometimes hard to resist installing them.

Games in particular can occupy more than 1GB each, so it won't take many before you run out of space. Plus, if you opt for an iPad Pro, iPad Air 2 or iPad mini 4 with an 8Mp camera, you'll probably take more photos and videos than you have envisaged.

There are ways to increase your iPad's storage. One is to buy a WiFi hard drive which works with iOS devices. You'll find examples here. However, you can't install apps on an external drive.

We're not saying that you shouldn't buy a 16GB iPad, but make sure it will be sufficient for your needs, since you can't change your mind later. iPads don't have a memory card slot for adding more storage.

Which iPad is best: Buy refurbished from Apple

A little-known fact is that Apple often sells refurbished iPads which are as good as new. Right now, you can buy a 128GB WiFi+ Cellular iPad Air 2 for £549, which represents a saving of £110. It's well worth keeping an eye on the deals, as they're always changing.

Refurbished models look like new, have a new battery and come with a one-year warranty, so there really isn't a reason to avoid them. The same can't be said of second-hand models bought from eBay or similar.