I wrote a post in April regarding the pros and cons of several cloud storage/backup service providers based on my experience, such as Windows Live Mesh, DropBox, Memopal, SpiderOak, and SugarSync, and I concluded that SugarSync is better than the others. Then you may ask what is the purpose of this post?

Well, it seems that many people are not happy with SugarSync because it does not have a native Linux client, so those people, especially Linux users, left SugarSync and chose either DropBox or SpiderOak. What I want to do here is to give a summary of the feature comparisons of the three service providers.

1. Backup

All three provide backup with recovery feature, but DropBox only backs up files in My DropBox folder on your computer. Both SugarSync and SpiderOak allow you to choose any folder on your computer to back up.

2. Sync with multiple computers

All three allow file/folder synchronization among multiple computers running their clients, but DropBox can only sync files/folders in My Dropbox on your computer. Both SugarSync and SpiderOak allow you to choose any file/folder on your computer to sync with another computer.

3. Easy to use

DropBox is very easy to set up and use. The installation process is simple and it will create a folder on your computer called My DropBox, and all files and folders will be synced automatically with other computers running the DropBox client.

SugarSync is also easy to set up and use. The installation process is simple and will create a folder called Magic Briefcase. Like DropBox’s My Dropbox folder, any files/folders in Magic Briefcase will be synced automatically with other computers running the SugarSycn client.The client also allows you to choose any folder or file on one computer to sync to another computer.

SpiderOak is not very easy to use. The installation process is simple and easy to follow, but it takes quite some time to understand  and to use the sync process. It does NOT create any folder for you, and it is up to you to choose which folder/file to sync.

4. Remote access

All three provide remote access to your files stored on their servers.

5. Security

All three provide encryption on your files that stored on their server, however, both SugarSync and DropBox claim that they have the ability to decrypt your files when needed for the legal purpose, because the decryption key of your files is stored on their servers too. SpiderOak, however, prevents anyone except you to decrypt your file, because the decryption key is not stored on their server, instead, the key is stored on your local computer when you install the client. If you are concerned about your privacy and don’t want ANYONE except you to be able to access your files, then you have two options:

1). Encrypt your files before you upload to their server

2). Use SpiderOak

If you choose SpiderOak, then you need to remember the risk: if you ever forget your password, then you will not be able to access your files any more, because your password is created locally and is not stored on their server, and there is no password recovery feature. Then you may ask, what if I forget my password? Here is the answer from SpiderOak:

Q #13: What if I forget my SpiderOak password?

At the time when you create your SpiderOak password, you will also be prompted to create a password hint. The creation of a password hint is not mandatory however it will be your only clue should you forget your password. If you choose to create a password hint, we advise you to create one that is informative enough so that you will remember but not too obvious so that anyone may guess. The password hint may be recovered anytime on the SpiderOak web page.

At SpiderOak we have created a true ‘zero-knowledge environment’ meaning that no one including the SpiderOak employees will ever know what you are storing on your SpiderOak Network. We can maintain this environment because at no time will anybody know your password (or the answer to your password hint) except you.

So I guess the zero-knowledge privacy comes with a price.

6. File sharing

All three allow file sharing, but the file sharing feature in DropBox is limited. You can only share files/folders in My DropBox folder, and all shared files from other people will be placed in your My DropBox folder. Both SugarSync and SpiderOak allow you to choose any file/folder on your computer to share with other people. The good thing about SugarSync sharing is that if another SugarSync user shared a file with you, then when you accepted the shared file, a folder called SugarSync Shared Folder will be created under My Documents (or Documents in Windiws Vista/7), and then a sub folder named after the user’s name will also be created to better organize files.

SpiderOak, however, is very hard to use to share files/folders. For instance, you will need to create ShareID and RoomKey before you can start sharing something, it is not easy I warn you.

7. Cross platform

All three support Windows and Mac platforms, but SugarSync is the only one that does not support Linux platform at this moment, I hope they will have a Linux client soon.

8. Mobile

SugarSync supports more mobile devices than the other two:

SugarSync: iPad, iPhone, BlackBerry, Windows Mobile, Android, Symbian.

DropBox: iPad, iPhone, BlackBerry, Android.

SpiderOak: iPad, iPhone, Android, N900 Maemo

9. Storage and subscription

SugarSync provides 5 GB free storage plus 500 MB bonus for each account sign up referred by you (no limit). It also provides paid plans if you need more space and more features.

DropBox 2 GB free storage plus 250 MB bonus for each account sign up referred by you (no limit). It also provides paid plans.

SpiderOak provides 2 GB free storage plus free bonus storage for each account sigh up referred by you (up to 50 GB). It also provides paid plans.

10. Upload / Sync via Email

Only SugarSync provides this nice feature. After you login your SugarSync account, click Account tab on the top, you will see your Upload by Email address under the Settings section:

If you send an email with an attachment to your Upload by Email address @e2f.sugarsync.com, then the attachment will be automatically uploaded to your SugarSync account and synced across your computers. You will find a new folder called Uploaded by Email is created under Magic Briefcase. I really like this feature because I can give my customer my Upload by Email address, and when they send attachments to that address, I will get them on any of my synced computer.