Last week, on the day it launched, I purchased an iPad Air. I had been looking forward to an iPad upgrade for a while, having spent the past 18 months on, variously, a 3rd generation iPad and a first-generation iPad mini.

My previous device was a black 64GB 4G iPad and my new device is a white 128GB 4G iPad Air. The difference is like night and day, and not just because of the colour.

I don't want to bury the lede here: the major story about the iPad Air is not the reduction in size and weight but the increase in performance. It is, to put it simply, an utter delight to use.

I'll talk about the rest later but let's talk performance first. The 3rd generation iPad was a particularly curious beast: it gained a retina display and the "X" suffix on its A5X processor to indicate its increased graphics power to handle the display. The odd thing about the 3rd generation iPad, though, was that it basically wasn't any faster than the iPad 2. It was still A5-based and still clocked around 250 GeekBench points on single-core tests and around 500 on multi-core tests.

The iPad line basically stepped off Moore's Law for a generation. There's a reason that the 3rd generation iPad was only on sale between March and October of 2012 and this is it.

The A6X-based 4th generation iPad resumed the exponential growth, checking in at 772/1408 GeekBench points for single- and multi-core tests. Too bad Apple screwed up by launching it at the same time as the iPad mini, such that almost nobody understood that it existed. Even eight months after its launch, I was still having clarifying conversations with people about which generation of 9.7" iPad we were actually on.

And there the iPad line sat for a whole year. Until now.

The iPad Air is the next step along the Moore's Law curve for Apple's custom SoC chips. The A7 processor is not, to be fair, an unexpected quantum leap. It's another routine iteration of Moore's Law - a doubling in performance over the A6 chip introduced 18 months earlier in the iPhone 5. The Air clocks in at 1471/2667 on Geekbench. What's different, though, is how this feels to the user.

I use an iPad literally every day and, when I'm teaching, as my main work computer. I am finely attuned to every aspect of the performance profile of the apps I use.

I know exactly how long Safari takes to bring up the keyboard when I want to search. I know exactly how quickly Tweetbot will resume and refresh the feed. I know how long Explain Everything will take to render a five-slide presentation. I know how long it takes for Keynote to open a particular file.

What I know about the iPad Air is that I'm constantly being surprised by these apps being ready and waiting for me as soon as I try them. I'm having to speed up my muscle memory as the iPad is ready sooner than I anticipate.

I notice this in two particular situations. The first is in launching and resuming applications. Multitasking on the iPad has been around for a while now and has grown in capabilities over time. There was always a small wait when switching between applications before the resumed app became active. In large part, that delay no longer exists - except for apps where the resumption depends on some network activity, such as launching Netflix from a cold start.

I have found that, as a result of this, I have become more willing to use the iPad for a complex multi-app workflow than I would have been with my 3rd generation iPad. Switching between apps no longer feels like quitting and relaunching apps; it feels like switching between multiple running apps - regardless of the actual implementation details behind the scenes.

The second task that is dramatically improved with the iPad Air's performance is rendering web pages in Safari. Someone on Twitter - perhaps unfairly - commented that the iPad Air is the first iPad to be able to scroll The Verge in real time. Complex web pages perform much, much better on the iPad Air and, as a result, doing complex tasks through the web in Safari is no longer as painful as it was.

An example just from today: we have a new pupil starting at school next week. To get them up and running, I have to create a new user record in my Google Docs spreadsheet, create a new Google Apps account for them, create a new WiFi password in our Aerohive network and print a number of forms for the pupil and their parents to sign.

In earlier times, that would have been a sequence of tasks I would have automatically reached for my MacBook Air to complete. Today, though, I just did them all on my iPad Air with no real additional effort or time taken. I'd say that the overall time for the task was about the same with some steps taking a bit longer (e.g. signing into 1Password on the iPad) but other steps being actually faster than on the Mac - for example, printing a form from Google Docs.

We are beyond debating whether iPad can be used for content creation. That discussion is over and those still arguing that it cannot are saying more about themselves than about iPad with every passing month.

I've written before about the relationship between task complexity and task duration as a way to think about the relative merits of smartphones, tablets and PCs. What the iPad Air - really, the A7 processor - does is push the iPad up and to the right of this chart, taking on ever greater and more complex tasks.

My current laptop is a mid-2012 13" MacBook Air. Previously, I used a late-2010 11" MacBook Air with a 1.6GHz Core 2 Duo processor and 128GB of SSD storage.

I'll leave you with this: my iPad Air is faster than that 11" MacBook Air and it has the same amount of storage. My iPad gets at least twice the battery life of that laptop and tips the scales at less than half the weight. It cost 65% of the price of the MacBook Air and has integrated cellular networking that can't be had on an Apple laptop at any price.

Apple's line on the A7 processor has been to call it "desktop-class". They're not overstating it by much.