Computing has become increasingly portable and mobile, with the internet playing an ever-increasing role in allowing people to avoid being tied to a single computer or location for work or personal purposes. One key factor in working here, there and everywhere is being able to access the latest version of your data quickly and promptly: if you work on a document in one location, will you be able to access those changes later on from another?

The emergence of the cloud has seen an opportunity for online backup services to evolve to meet the needs of people who need to either access their data from multiple locations, or who wish to be able to share files quickly and easily over the internet. We take a quick look at three such services – Dropbox, Wuala and Windows Live Mesh – in this feature.

The basics of synchronisation
While tools for synchronising folders are nothing new, the likes of the Windows Briefcase or a file-sync tool like Allway Sync rely on either both computers being switched on and connected to the same network, or an intermediary device such as a USB drive. It’s workable, but it’s not intuitive and relies on you remembering to synchronise each time.

Far better then, to utilise a cloud-based service: this automatically backs up or synchronises selected folders to the internet as they’re updated. Then, when you log on at another machine, the service in question silently downloads those updates to your current computer, ensuring you always have access to the latest versions of your files without having to remember they’re there.

An added bonus of this approach is that your files are also being backed up to the cloud, so they’re in a minimum of three places at once, making it less likely you’ll suffer from data loss. The downside is how much online storage space you get as part of your service.

Windows Live Mesh
There are both free and paid-for services offering this cloud-based sync feature. Windows Live Mesh is the most visible free service, offering 5GB free online storage that can be shared across both Windows and Mac computers. Folders can be synced directly between computers as well as via the cloud, thus allowing you to rationalise your storage space for those folders you access frequently.

Windows Live Mesh also allows you to access your files from the web – giving you universal access to them – and it features Remote Connection, allowing you to access your computer from another location if it’s switched on and connected.

It’s installed as part of Windows Live Essentials, so make sure you choose the selective option unless you want all the other Windows Live apps too. It also requires Windows Vista or 7 on the PC, so XP users are locked out.

Dropbox
Dropbox offers a cross-platform solution with mobile and Linux options in addition to Windows and Mac. It offers similar features to Live Mesh – online backup, sync, web access – but only provides 2GB storage space as part of its free Basic package. Paid-for solutions are expensive (US$9.99/month for 50GB, US$19.99/month for 100GB).

Dropbox does have several features not found in Windows Live Mesh, and these are available to Basic as well as premium accounts. First, online backup stores multiple revisions of files, allowing you to restore older versions. And second, you can share folders or photo albums with selected people or the wider internet, allowing others to not just access your files but collaborate on them too.

There’s also an “undo” option – as all changes are quickly synchronised with the Dropbox server, you might find you’ve accidentally deleted the wrong file or made a change you’re not happy with. Don’t worry: Dropbox stores up to 30 days of revision changes, allowing you to undo them quickly and easily.

Wuala
Wuala’s service comes in free and professional versions. The free version offers a rather basic 1GB package, principally for media streaming and sharing. Other features – backup, sync and file revisioning – are restricted to Pro accounts, but these cost a lot less than Dropbox, with prices starting from just €19/year for 10GB storage space. There’s no undo feature as found in Dropbox, but all deleted files are sent to the Trash, so you can recover anything you accidentally delete.

Wuala also boasts a rather unique feature: the ability to trade storage. If you’re online for a set number of hours per day, Wuala will offer to give you a Pro account with a set level of storage in return for using the equivalent amount of storage space on your hard drive for encrypted backups. Once you’ve been running Wuala for a short while – and assuming you pass muster – this offer will be made to you or you can click the “Go pro” link within the main program window and select Trade. This way, it’s possible to get all the pro-level features without having to spend a penny in hosting fees, but read all the terms and conditions before you start.

Which service is for you?
Windows Live Mesh will appeal most to those with relatively small demands who merely want to synchronise files between two or more computers without having to pay a penny. Dropbox’s 2GB account is enough to get familiar with the service, but the high cost of upgrading to its professional features will be off-putting to many, particularly when compared to Wuala. It does, however, support multiple mobile devices including Android and iPhone, something neither Wuala nor Live Mesh currently do.

Ultimately, however, we’d have to say that Wuala is currently our cloud-based sync and sharing service of choice: the desktop application works well, and its range of features and comparatively good value (exceptional if you’re able and willing to trade storage space on your computer) make it well worth considering if you’re looking for online backup, sync and sharing in a single service.