I think concurrent editing is where Dropbox collaboration falls down. E.g: you edit the intro paragraph, and your buddy adds a conclusion, both while offline (

I think concurrent editing is where Dropbox collaboration falls down. E.g: you edit the intro paragraph, and your buddy adds a conclusion, both while offline (or simultaneously). Dropbox can't/doesn't resolve the conflict in your files, and instead picks a winner. This is still solvable by your app, but requires additional logic/storage above what the "shared folder" model provides.