Hi Guo,
* Image Processing Service
Currently we don't provide api to detete images, but you can delete from AppHQ console.
Currently uploading images for Image Processing Service through AppHQ Console is not part of our recent releases. We will update you once we release it.
* Upload File Service
Yes we have multiple api to delete file like removeFileByName(), removeAllFiles(), removeFileByUser() etc
for more details seen the api docs.http://api.shephertz.com/app42-docs/file-upload-service/