When I started my journey with Knack, I placed all my application images in Dropbox.
Not the application files but the logos that are user facing on pages.
It was a long time before I realised that it would make more sense to save them in an object. 
You can then set various thumbnail sizes and have a hidden collateral page so you can create the links directly from your images in AWS. If you already knew this, then I apologise, otherwise, I hope its helpful 
