Since Android 6 (Marshmallow) it is no longer possible to clear cache of all apps at same time and Google has moved this permission to system apps only. There is only one possible way left - open manually info about application and find specific "Storage" menu and then press "Clean cache" button.
Cache Cleaner can request all installed user and system apps and it replaces all manual actions related to clean cache using Accessibility service.
Cache Cleaner saves the last checked apps to show them next time only.