The best way is to insert an uploader to your dropbox, google drive or onedrive account.
For example for dropbox, follow these instructions:
1) Go to http://www.dropitto.me/ and register for a free account.
DROPitTOme to create a personalized URL in which you or other people can upload files directly to your Dropbox.
You get to set a password to this URL, and only people who know it may access the uploading section.
Your dropittome personal url would be something like this: https://dropitto.me/xxxxxx
2) Add "Link" module/functionality to your App.
3) Copy and paste your dropitome url here.
The files are uploaded to My Dropbox/DROPitTOme and that’s it. You can’t create folders or organize it in any way.
