are you testing features?
if so, you can easily build out screens inside of your mobile app (alternate screens) and before loading the screen check with your server on which one (path) you should load ...
I think dropbox is great and non intrusive but this presents 2 challenges
1. Since dropbox is almost in the background, it's much easier to forget about it, than my gmail and google docs (google drive's integration with it). I think this means that I will adopt google drive sooner than i would like to admint and slowly start forgetting dropbox because it's too non-intrusive
2. What will this do to new user adoption for dropbox? google drive is clearly visible ...
i think dropbox should quickly scale up enterprise level activations and the non google dependent users ...
also might help them to develop new strategies to start holding on to people, becoming a bit more visible ...