Pros
Cons
Our Verdict
In many ways, computer filesystems are relics of days gone by. Documents get lost, misplaced, and disappear seemingly without a trace. To further complicate things, almost everyone nowadays uses multiple devices, which forces us to play an even more complicated game of “Where did I put that file?”
Doo ( Mac App Store link), developed by the German company of the same name, aims to address this problem. Doo aggregates all your documents regardless of where they come from and are stored, and analyzes them to create a database of interesting features that can later be searched and synchronized among multiple devices.
Installation
At this time, Doo supports both OS X Mountain Lion and Windows 8. On its website, the company also states that versions for Android and iOS are coming soon, although no specific timeframe is given.

Installing Doo on my Macs was, by far, the most frustrating part of using the app. This was due to the fact that almost all my machines contain multiple hard drives, and that my home directory is in a non-standard location—both conditions that Doo doesn’t handle very well out of the box. Luckily, the company addressed this shortcoming in version 1.0.5, which is currently available as a free beta on the Doo website. (Doo currenlty does not support external storage devices.)
Once past this problem (which seems to have frustrated many an App Store user, given the product’s reviews), getting Doo to run was as simple as installing any other app. After choosing a directory where metadata about indexed documents is stored, I had the option of specifying one or more sources of data where Doo would go looking for documents to analyze.
Documents, documents, documents
Even to someone who has been around computers for a while, Doo’s ability to find and index data is quite impressive. The app supports many different sources of data—not just the obvious choices like local folders, but also email accounts and several cloud providers such as Dropbox and Google Drive.

In all cases, the process of adding new sources to your account is completely seamless and easy to use; not once was I asked for more than a username and password, and Doo was able to immediately discover all the appropriate settings required to add my email account, which uses an obscure mailserver, on its own—something even Mail hasn’t been able to do over the years.
Once a new source is added, Doo starts to index its contents right away. In some ways, this is similar to what Spotlight does, but with some significant differences. Where Spotlight relies on apps to provide metadata on each document it finds, Doo employs its own indexing algorithms that, in some cases, go well beyond what OS X’s built-in search engine can do. For example, when Doo encounters an image, it actually attempts to perform optical character recognition (OCR) on it to determine whether it contains any text that can be analyzed and used later in a search.
Search and retrieval

Doo organizes documents according to a variety of automatic tags that identify their characteristics. In addition to analyzing common attributes like file type and creation date, the app can, for example, automatically detect the names of people, companies, and places mentioned in them, and even make a reasonably intelligent guess as to the nature of their contents.
These tags can then be used to construct a query together with free-form text, allowing you to, say, find all the résumés that mention a particular person, or the contracts that reference a particular place, and so on, adding a layer of knowledge that goes well beyond what Spotlight can do.
Doo’s OCR capabilities come in very handy here, as they are able to find references inside documents that are not normally well-indexed by other search engines. As an example, during my tests I found a scan of a contract from several years back that I thought had gone completely lost (alas, Doo would have been very useful a year ago, when I was actually looking for that agreement).
Cloud features

In addition to its uncanny ability to index and retrieve documents, Doo comes with a feature called Doo Cloud that allows the app to back up the documents you choose to cloud storage so that they can become accessible from other devices on which Doo is installed. This premium feature comes with a free gigabyte of storage; additional space will be available at prices ranging from $5 to $25 a month, although the publisher hasn’t yet announced a launch date.
At the moment, this feature is really only useful if you happen to own multiple Macs—like, say, one at home and one at work—and can’t easily sync data between them using another method, such as iCloud or Dropbox. As Doo becomes available on more platforms, however, the ability to automatically collect, index, and keep documents on all of them synchronized should come in very handy when you need to get quick access to a document while on the road without your computer.
Bottom line
All in all, Doo is an excellent product already above the competition in how it combines simplicity of use with power. Still, it’s a product that can, right now, only be adopted with an eye towards the future. In the immediate, its usefulness is limited by lack of support for iOS and Android, where Doo’s cloud feature would be most useful, and also by the kinks that inevitably affect new products and still need to be worked out.
With a little patience, however, you will find that Doo has the potential to dramatically change the way you organize and find your data, and it can only get better as it grows into a fully mature product. Doo is free and can be downloaded directly from the App Store or from its publisher’s website,