Note: if your device is not rooted, the app can only perform a "limited" scan for for deleted photos. To be able to search for other types of files, and to search your device's entire internal memory, the device needs to be rooted. On a non-rooted device, the app can only recover lower-resolution versions of your photos that it finds in your device's cache and thumbnail directories.
For complete instructions, please see http://diskdigger.org/android
You can upload your recovered files directly to Google Drive, Dropbox, or send them via email. The app also allows you to upload the files to an FTP server, or save them to a different local folder on your device.
DiskDigger can recover the following file types: JPG, PNG, MP4 / M4A / 3GP / MOV, GIF, MP3, AMR, WAV, TIF, CR2, SR2, NEF, DCR, PEF, DNG, ORF, DOC / DOCX, XLS / XLSX, PPT / PPTX, PDF, XPS, ODT / ODS / ODP / ODG, ZIP, APK, EPUB, SNB, VCF, RAR.