You can choose and insert any file you have hosted in your Dropbox account. Depending on the type of file you choose, Dropr will give you different options to insert the files.
If you choose an image file (JPEG, GIF, PNG, etc.) you will get options to add title, caption, alt and link.
If you are choosing a document file (PDF, DOC, PPT, XLS, etc.) you can embed them into the content using Google Docs Viewer or Microsoft Office Online Viewer.
Videos can be easily embedded from your Dropbox account. Uses standard WordPress video shortcode. You will get options to add alternative video file types for added HTML5 browser compatibility.
Audio files can be embedded from your Dropbox account. Uses standard WordPress audio player shortcode.
Other file types
All other files can be added either as plain links or buttons. Even there you will get plenty of options like customizing button style to changing click behavior.