The problem with sharing files over the internet is that everything is permanent. Digify doesn't fix this issue, but it sure attempts to by taking the Snapchat approach to privacy and applying it to files. Rather than giving someone permanent access to a document, it gets a time limit from the sender and initiates a self-destruct at said time. It even goes so far as to provide information on who has opened the file and how long they've interacted with it. For the sake of convenience, users can also browse Dropbox and send a file all from within the app.
Digify is smart enough to block the ever powerful screenshot command, and it shoots up a notification whenever such an incident occurs. Of course, someone could still get around this by taking a picture of the screen using some other camera, and another determined individual will probably be able to come up with a workaround using root access. So Digify still may not be quite as secure as the previous self-destruct method shown off in the trailer.
Nevertheless, the app provides a stringent set of controls, letting owners prevent recipients from downloading or sharing the files they've received. Time limits range from one minute up to one month, and senders are free to delete the files at any time. To top it off, all of this is available for free.