UPDATE: The information in this article is now mostly obsolete. It was accurate when the article was published but Dropbox has since greatly improved its security by adding industrial-strngth AES encryption that is equal to or better than that described in this article. Details may be found at https://www.dropbox.com/help/27/en.
I will lkeave the old article here for historical purposes:
I have written several times about Dropbox, an extremely useful program. If you use one computer, Dropbox can be useful. However, if you use two or more computers, such as a desktop system and a laptop system or perhaps one computer at home and another at the office, I'd consider Dropbox to be indispensable. It will automatically copy the files you specify between the two or more computers, making sure the computers are always in sync. It is a great way to make sure your files are available to you all the time.
Dropbox also keeps a copy on the company's own web server, protected by a user name and password you create. As a result, you can even retrieve any of your files when you are traveling by using a borrowed computer, an iPhone, iPad, Android device, or most anything else. The result is that you always have a backup copy of each file you specify. Dropbox also can share some or all of the files with people you specify, such as with friends or relatives. In fact, I find Dropbox to be much easier and convenient for sending files and digital photographs to someone else than by sending the same things as attached files in email. Dropbox is especially useful for sending large files that are too big for email attachments.
Dropbox has more than 100 million satisfied users, including myself. However, a few people will not use the program because they are concerned about the security of saving their files in the cloud. There are several possible solutions to that concern but perhaps the easiest solution lies in a newly-announced product called Viivo.
Viivo provides file encryption to safely share and store files in the Cloud. The new program adds AES 256-bit encrypted files, the same level of security used by banks, stock market services, the government, and others to make sure information is kept from prying eyes. I figure if the security is good enough for the government and for banks, it is probably good enough for you and me. With AES 256-bit encrypted files, not even the Dropbox employees can read your files, should they try to do so. Hackers also will be locked out. The best part is, if you know how to use Dropbox, you already know how to encrypt files using Viivo.
The new program is available for Windows, Macintosh, iPhone/iPad/iPod Touch, and Android. Of course, the most important item of all may be the price: FREE for both personal and commercial use. Viivo allows you to always have your sensitive files with you and yet feel confident that they stay encrypted on your device. You don't even need to supply a credit card number to download and install Viivo.
Viivo was created by PKWARE, the company that invented the .ZIP file back in 1986. Since then, PKWARE has created many other programs to add convenience for computer users. Viivo is the latest addition to the list.
For more information, or to download the FREE Viivo program, go to http://viivo.com/.