Both FileFox and FileDrop let you attach files to Google Sheets, but they take different approaches. FileFox is a drag-and-drop file manager that uploads files to your own Google Drive and shows automatic thumbnails or file-type icons directly in your cells, so you can identify any file at a glance.
If you want a simple, visual, Drive-native way to manage files inside Google Sheets without locking your data into another vendor, FileFox is the more transparent choice.