Of all the apps I have installed on my iPad, Flipboard is probably the one that has had the greatest impact on my digital life.

Prior to getting my iPad, I used to view my Facebook and Google Reader feeds via Socialite on my MacBook, and Twitter via the Twitter App for Mac of iPhone, depending on where I was.

Flipboard has now taken over from all the above.

It sucks in all of the above feeds, and produces a personalised ‘social magazine’ that just looks great on the iPad. Twitter links are sucked in, so that the linked webpage is transformed into a magazine article, while non-linking Tweets just appear. TwitPics appear as pictures in my magazine. It really is quite incredible, and very fast – probably quicker to refresh than the Twitter app on my iPhone.

But, importantly, it doesn’t just look good – it is brilliantly functional.

Flipboard allows me to cross post anything anywhere, so I can share that interesting Tweet on Facebook or post that interesting article from Google Reader to Twitter with just a tap. You can also elect to ‘ignore’ people, without having to ‘unfriend’ or ‘unfollow’ them, which comes in handy.

Flipboard is now the primary way I interact with all of the above feeds. It’s brilliant.

Brilliant, but not perfect. I’d like to see threading of conversations on Twitter. I’d like to see whether Facebook statuses had comments without having to tap on them. I’d like Flipboard to see which Twitter and Facebook updates I’ve read and hide them, like it does with Google Reader (unless they have new comments). I’d really like Flipboard to learn what I like, and push those things to the front of the magazine rather than absolutely sticking to the timeline.

But still, Flipboard is great – in fact, I think it’s my favourite iPad app to date. I’m confident it will retain its place in my Dock for some time to come!

This is the fifth and final in a series of posts reviewing iPad Apps. Yesterday’s review was of Who Wants to be a Millionaire HD. If you enjoyed the series, let me know in the comments or on Twitter (@sjhoward), and maybe I’ll do something similar again sometime.

But that’s it for now… Stay tuned for more posts on different topics coming soon(er or later).

Flicking through my Twitter feed this morning, I noticed something about Google prophecying about applications soon been independent on the devices on which they run. I didn’t read any further, but the idea obviously seeded somewhere deep in my cerebrum, as it has been playing on my mind all day.

My initial reaction was “rubbish”. Web based apps are great – I’m a big user of Google Docs – but they’re far from device independent. I can access my Google Docs from anywhere, any computer, and even on my BlackBerry. But I’m not clinically insane, and wouldn’t try and write a dissertation on a BlackBerry. The application might work on one, but that’s not device independence.

But then something occurred to me: Email.

Not so long ago, I used to use Outlook Express to access my email at home. And for a while afterwards, I flirted with various versions of Outlook, Opera, Thunderbird and many others.

In my early years at uni, I had Outlook on my computer and a ZZN email account which would poll the various email servers I used and pull in copies for me to browse on the go when I was away from home.

Later, I had an iPaq – it seems so old worldly now, but it had no wireless or mobile connection. I would only get new email or send emails when it synced with my computer.

For a very long time, my computer was the centre of my email universe. That is no longer true.

Email is one application that is genuinely device independent. My Gmail is pushed to my BlackBerry, but if I’m sat at a computer I’m equally likely to just click onto a browser and access it that way – without a second thought.

I can access it using any computer with equal ease, and with full functionality. Due to their relatively short nature, I’m equally likely to tap out a reply on my BlackBerry as I am to reply via PC.

The idea of waiting, as I did only 5 years ago or so, until I get home to check my email seems hopelessly quaint and antiquated.

Is this level of unity gifted by the nature of email as an application? Or can Google (or anyone else for that matter) replicate it for other functions?

I wouldn’t be so quick to rule it out any more.