It seems that after Dropbox started the trend of personal cloud storage, most major players joined the game. Last couple of weeks, Microsoft, Google and Amazon completed their existing offerings with the desktop syncing app they all needed to have in the first place to be really useful as cloud storage. To me, cloud storage looks like the next big consumer cloud service after e-mail.
A careful examination shows that all vendors offer the main features like web access, PC sync and mobile apps, but they differentiate in some important aspects:
Free space is what you really get if you sign up for a new account. Various vendors offer referral bonuses and others give you coupons which increase storage space temporarily or for life. If you had an account when Microsoft launched their SkyDrive desktop app in late April, you got to keep the initial 25 GB quota that is now 7 GB for new users.
Price for extra GB (yearly) is what you’d pay if you needed more space than the free offering. The price in the matrix is calculated based on 20 to 50 GB upgrade packages. If you buy more, you might get a better price per gigabyte. Far from the rest, Microsoft scores better in this department with only 0.5 $ per gigabyte.
PC Sync (Windows and Mac) means one can install an app that syncs all or part of your files between the cloud and one or multiple Windows machines or Macs. The main benefits here are: backup (through file versioning and cloud recycle bin, faster file opening times and offline access.
iOS and Android apps allow you to access your files on the go and in some cases also upload files from other mobile apps to cloud.
iOS and Android offline access give you the opportunity to download some files locally on the device so you can access them when you don’t have connectivity, for example when abroad or on the mountain.
Web access gives you access to your files from a browser using your username and password.
File versioning keeps previous versions of files so you can restore them later. The majority of services offer full file versioning, while others version only specific document types (Skydrive for Word and Excel documents).
User Encryption happens before files are uploaded to the cloud. This means that the provider does not have access to actual content of users’ files, adding real privacy, at the same time making web access and sharing a bit more difficult.
Anonymous sharing – READ is when you can send a link to a file or folder for other to access without requiring sign in. This makes sharing not so confidential files very convenient.
Anonymous sharing – CONTRIBUTE is a special kind of sharing currently offered only by Google Drive which allows filling in a list with information from multiple unauthenticated contributors.
Sync shared folders allows a group of people to work on sets of files on their own PCs or smartphones. However, concurent access usualy results in conflicts and results in multiple instances of the same file, requiring manual merging changes. A solution for concurent access to files is offered by Google Drive and Microsoft Skydrive by means of web access).
Web recycle bin keeps deleted files for a specified period of time in the cloud, regardless of where the files were deleted: either on PC or from web browser. Although Skydrive does not offer this, you have the desktop recycle bin regardless of where the files are deleted: either cloud or PC.
Choose subfolders to sync is a feature that allows you to sync only a subset of your cloud folders to PC. Say for example that you uploaded some files to the cloud for archival and you don’t want them synced to the PC to occupy disk space.
VIEW documents in browser allows you to read specific document types directly in the web browser, without the needing to be downloaded locally. This is useful both for opening your own documents on a foreign PC and for sharing documents. For example, the comparison matrix above is embedded into blogger from Skydrive so I can simply update the excel document locally on my computer and it automatically updates in the blog post.
EDIT documents in browser allows you to edit compatible documents without having the application installed on PC. Say for example Excel files – you don’t need Office to create and edit basic spreadsheets.
Block level sync is a feature currently only offered by Dropbox that syncs only the parts of files that have been changed, saving both time, bandwidth and most probably space in Dropbox’s datacenters. One benefit of thiis feature is that you can store truecrypt data files in Dropbox and only the modified bits of data get transfered over internet when the drive is dismounted.
Auditing shows the centralized history of modifications to files by you and the people you share files with. Only Dropbox currently has this feature.
The API allows access to the cloud service by other apps.
Sync multiple folders means you’re not limited to one folder in which you must store the local replica of the cloud storage. You can select multiple locations on different disks/partitions to sync to the cloud.
Small footprint desktop app means that installing the desktop app won’t slow down your computer too much. Worse case scenario are memory leaks that I’ve noticed in Wuala.
Share with a password allows sharing with a bit of extra privacy. For example, one can send the link to a folder by e-mail and communicate the password by phone.
Please feel free to comment and vote for your favourite: