I'm trying to develop an App whose purpose is to share files in my smartphone with some friends, kind of Dropbox. I have a FileObserver watching a directory and when any change is applyed to one of its files, the App should read and do some stuff with it, write the result in another different folder and upload it to a server in order for my friends to get them when they sync in their smartphones using, obviously, the same App.
I've been taking a look at Dropbox API but I think it's not possible to programme something like that, I don't know with Google Drive.
The thing is, I've come across Google Cloud Messaging and wondering if this could be the solution I'm looking for.
So I'd like to know if this is possible with GCM and how it could be done. If you know another way to do so it'll be welcome.
Thanks in advance.