Overview: A small client gets installed on computer A and computer B. Files added to computer A are synced to the Dropbox cloud server, which then syncs the files to Computer B (and any other subscribed computers). The presence of the files on the Dropbox cloud server has the side benefit of being able to easily access the files online, and even share URLs for people to access the files without the Dropbox software. It went a long way toward solving the problem of "I need have access to my files on many different computers, tablets and my phone, and occasionally make these files accessible to the customer". However, it's simple installation and accessible marketing seems to have led it into another use case, and not necessarily one that it is good for: sending files to other users.
There have been countless online services, yousendit.com, megaupload.com, filestube.com, to name a few, which do a pretty good job of this use case: "I have a 2 GB file, I need to send it to firstname.lastname@example.org." However, it seems like most people don't like uploading the file to a website, getting a URL, and then pasting this into an e-mail. Perhaps it's the extra steps, perhaps it's a concern about putting the file on a third-party site (which is ironic, as Dropbox does the same thing, but for some reason people don't get this).
The possible issues with using Dropbox this way are many. Here are a few:
- Dropbox is a comparatively long-term relationship, as opposed to e-mailing a URL. Once a shared dropbox folder is on your systems, it will be there until one of you removes it, which requires some consideration.
- When you have a Dropbox folder with someone, the folders stay sync'd. The idea of sending a file this way implies that either of you will remove the file after the transaction. If this is done by the sending party, the receiving party had better have copied the file somewhere outside of the shared folder. Likewise, if it's done by the recipient, the sender had better be expecting it. If it's done by no one, you now have a file there with no clear owner, which will eventually become either out-of-date or irrelevant, and that might be a complicated situation when it comes time to clean up.
- Dropbox sharing with other users doesn't scale well. Once you start sharing with a number of people, it's difficult to keep track of which folders were shared, with whom, and whether the elimination of a folder on your system will impact others in a negative way.
- Dropboxes grow in size on the sender's computer - keeping files in a Dropbox so that they are available to others means that you have to have sufficient room to store those files, which may mean having duplicate copies, if you wish to freeze a file's version for example.
- Dropboxes grow in size on the recipients's computer - imagine what happens when your dropbox buddy "drops" a 2GB file on your system drive, that has 1GB free. This happened to my friend a few months ago when he wasn't even around, and it wasn't pretty. When trying to mitigate the lack of space situation, he ended up deleting some huge files from the shared folder, which of course deleted them from the sharer's computer as well!
I have no problem with using a URL to share particular files or folders in a Dropbox, other than the caveat that anyone who knows the correct URL can access your "private" files (something a lot of people don't seem to acknowledge). The transfer of a URL in an e-mail is non-committal enough that I'm not going to worry if someone can't get the file when I deleted or moved it a month from now. I just don't like the trend I'm seeing of people installing Dropbox clients, just so they can get a shared folder a business associate sent them.