Humyo can be used as a web-only tool, and with the free version this is the only method of operation. If you upgrade to the commercial package, the client software is available to simplify the process of uploading your files.
Only 10GB of cloud storage space is provided free of charge, but this can be upgraded to 100 or 250GB if required. When it comes to dealing with files that have been uploaded, the Humyo site can be used to browse images and play back media files without the need to download them again.
Some filesharing options are also available, but again only to users of one of the paid-for accounts. Although there is no real online file editing functionality, uploaded files can be opened using the associated program and edited on a local machine.
When changes have been made and saved, the edited file will be automatically uploaded. This does have the advantage of providing access to the full feature-set of the relevant editing program, but it's slightly less convenient than dedicated online editing.