This article was written in the 2014, there may have been some developments in the subject matter.
If in doubt please leave a comment in the bottom of the article.
Anyone who has used Ubuntu at least once in the last years has made the case for Ubuntu One, the cloud service offered by Canonical natively installed on recent distributions of Ubuntu. Ubuntu One is exactly what you would expect from a cloud storage service and so far has winked to all Ubuntu users sometimes left without support from direct competition.
Exactly as Dropbox, SkyDrive, Google Drive, Mega and company allows a subscription for manage a web space remote. The free Basic plan starts from 5GB, acquiring additional functionality, or enrolling their acquaintances through affiliate links is Upgrade to permit storage space always higher. Ubuntu One Music Store (managed by 7digital) allowed instead of buying music formats MP3 DRM-free, then imported into all connected devices.
Last 2 April a statement on the Canonical Blog however, triggers reactions of various kinds (I do not remember to have seen so many comments on that blog). Apparently Canonical close the service. Subscriptions to the service are already closed for all registered users the service will remain active until the 1 June 2014, while downloading content can be loaded up to 1 August. Canonical reimburse all users who have subscribed to a paid plan expires after the 2 April.
As reported by effectively Wikipedia, Ubuntu One as well as being a cloud storage service is also a client to connect to the remote drive. The licenses of the two "products" however, are different. While the client is open source, all software for managing files on the remote server is owner. Always on the page of the press release explains that the service will soon be discontinued, but it would not make sense not to release the code that handled user files. You will then be issued with an open source license as soon as possible (probably hosted on launchpad) and will be published by another post.
The fate of the client is already marked: by the new updates users Ubuntu, Android and iOS will download a new client that will notify them of the imminent closure of the service. Obviously in the next release (14.04) Ubuntu One will not be installed.
As for me I have used the service of Canonical no problems since shortly after its launch. I synchronized no problems my files between different devices and I activated a backup contacts and photos taken with my Android phone. I understand, however, that the revenue derived from Canonical for most from the support that provides, has been very little gain from Ubuntu One, which still remains a good product, but that was addressed to a user already incentivized to spend little / nothing (Ubuntu stessa è open source... and let us not that the world we are all advocates of freedom).
On the other hand I believe that the closure of Ubuntu One does not fault. There are dozens of similar services, and often the GB offered are more than 5, many also have a client for Linux that will not be comfortable / integrated as Ubuntu One, but it will work the same way. Not to mention that the launch of the Ubuntu distribution dedicated to mobile is imminent. I understand that the labor force (already reduced to a minimum because of the already meager income of Canonical) be increased on the things that Canonical itself has always focused: do a good operating system.