Raise your hand if you use the cloud-based file-sharing service,. Keep your hand up if you know that Dropbox saves versions of all the files you store in it so you can recover both deleted files and older versions of modified files. Now keep it raised if you have ever recovered a file using Dropbox’s Web service. If, when I asked any of these questions, you had your hand up, you might be interested in  from Bayesbits Ltd.
Revisions is a Mac utility that watches your Dropbox folder and keeps track of what is going on in it. Click its menu bar icon and you can see a timeline showing all the activity that has taken place in Dropbox, starting with the most recent. Use the menus in the Select a Folder section at the top of the window to view changes within a particular Dropbox folder and its subfolders. You can set the span of time that the timeline covers with the controls in the Filter by Date section, just below Select a Folder.
The timeline itself is presented in the third section from the top: View Activity. Each individual item in the timeline represents a single change, called an “edit,” to a file in your Dropbox. By default, Revisions collects edits into temporal chunks, called “groups,” for convenience. You use the Group Threshold slider above the timeline to set the time covered by a group, ranging from no groups at all to groups that collect edits over 5-day spans; the mid-point on the slider creates groups that cover 10-minute spans of activity.
The edits listed in a group fall into four categories: created, modified, deleted, and temporary. For all but temporary edits you can click icons following the file name to view the file as it existed at that time, download it, undo the change represented by the edit, and, for modified files, compare it with the next version of it saved in Dropbox. In case you can’t remember what an icon does, hover your pointer over one to see a help tag that describes its function. By the way, the light gray appearance of the icons may lead you to think they are disabled in compliance with the long-standing Mac convention, but that is not the case — they are gray simply to be less distracting: if the function that an icon represents is disabled, the icon simply doesn’t appear in the Revisions timeline.
In addition to individual edit actions, each group has an undo icon in its top-right corner: click that to undo all the changes contained in the group at once. Don’t be afraid that you might accidentally click it and mess things up: all changes, whether to an individual edit or an entire group, produce dialogs telling you what is about to happen and asking you to confirm the changes.
What about temporary edits? They represent modifications to files that have taken place within the time that the group represents and are purely informational: no icons follow the file name in the timeline for temporary edits. If, however, you need to act upon one of these intermediate edits, select the group and click Ungroup to see each edit individually in the timeline, at which point you can act on one of them.
When you move your pointer between two adjacent groups, the timeline opens up to show two more icons. One allows you to download the currently displayed Dropbox folder and its subfolder to your Mac in the state that it was in before the edits began in the most recent group of changes (that is, the group above the icons); the other restores the currently selected folder to its state just prior to the edits shown in the group above.
The free version of Revisions can do everything I’ve just described. If, however, you purchase the $9.99 in-app upgrade to the Premium version, you get some additional functionality. Premium provides the capability to filter files shown in the timeline by name; for example, you can choose to show edits involving
.html files only, or just edits involving files that contain “TextExpander” as part of their names. If you use shared folders (and, boy, do we use the heck
out of shared folders at !), Premium shows you who among the users who share a folder has performed a particular edit.
Of course, you can undo file changes and recover previous versions simply by going to the Dropbox site and performing your there. However, Revisions provides a far more navigable interface for such activities, with more information about individual edits. There is no magic involved: Revisions works from the very information that Dropbox maintains so that it can provide its capabilities; the app just displays the information provided by Dropbox in a more flexible and useful fashion.
If you regularly use Dropbox and want an easy way to revert file changes or even just to see what you’ve been doing in Dropbox, the free version of Revisions may be just what you want. And if you use shared Dropbox folders and need to know who has been doing what in them, the in-app upgrade to the Premium version is just a click away.