OneNote for iPhone has finally reached the UK and marks the first time the Brits can officially use a Microsoft Office tool on an iOS device. Available for free (initially), it even improves upon the US edition (which has been out since January 2011), being version 1.2.

Obviously, OneNote has been integrated into Windows Phone 7 for a while, and it'll see improvements when Mango's ready, but that news has been scant consolation for iPhone-carrying SkyDrive users. Thankfully though, they too can now join in with the note creation fun (yep, we really did "note creation" and "fun" together).

For Americans who are sitting smugly and wondering why the excitement, even your version is now vastly improved with new functionality, including the ability to search across recent notebooks, image capture (which, like everything, will sync across your cloud-based notes to appear instantly in desktop of web app versions of OneNote) and access to shared notebooks.

But for the rest of us, and by that we also mean Ireland, Australia, New Zealand and Canada, this is pretty new. It's also, if you've only managed with Apple's pre-installed notes application until now, pretty essential.

To begin with, a Windows Live account is mandatory, as the point of OneNote is that you store your files remotely. You can then access and manipulate them through Office 2010 with OneNote installed on a PC or via the free web app (found at the top of your Hotmail homepage) too. Indeed, as the iOS application is designed specifically for a smaller, less powerful device, you may find that it's easier and quicker to create complex notes on a computer first, and then sync them to your phone.

And that's exactly what we did in our hands-on in Microsoft's London office. Chris Adams, Office product manager in the UK, sparked up a note he'd created earlier (of locations in Washington he'd like to visit on his honeymoon) which contained a map and a checklist, and we got to see, using the iPhone's own camera, how the whole shebang syncs immediately across platforms, including the aforementioned web app.

Adams used his iPhone to take a picture of a friendly volunteer and inserted it underneath a new listing in his Washington sights note. After 20 seconds or so, he then opened the same note in the web apps version of OneNote, which had changed to incorporate the new text and picture, and then the desktop version, which featured them both likewise. Simple and (nigh-on) immediate.

He also showed us the new search functionality on the handset, which will now search throughout all of the "notebooks" and come up with individual notes, as well as group headers. And this was all performed on an iPhone 3GS, with no speed issues whatsoever.

Of course, there are other note-taking, scrapbook creation apps out there, Evernote being a particular fave of many, but not only will Microsoft's be essential for any iPhone owner who uses Office 2010 on a PC, it seems that the software giant has addressed the issues and glitches with previous builds that were reported over the pond.

Incidentally, although the iTunes page claims compatibility with the iPad, you should be aware that it is only compatible in the sense that it will work much like a lot of non-universal applications; in 2x screen mode. It's something that could be addressed in the future, however, as Microsoft exclusively told us that if enough people call for a native iPad app, the company will consider one.

We also understand that this could just be the start of a wave of Microsoft Mobile Office applications for the iPhone and other devices.

OneNote for iPhone is available as of today on iTunes.

What's your favourite note applications on portable devices? Let us know in the comments below...