DiskWarrior - DiskWarrior, the world's most advanced and highest rated hard disk, hard drive, and disk repair and data recovery tool for macOS, OS X and Mac OS X.
DaisyDisk - DaisyDisk is a disk analyzer tool for OS X that visualizes hard disk usage and allows to free up hard disk space.
Data Rescue - When Apple's system recovery fails, recover any and all files with Data Rescue 3. This data rescue software will even work if your Mac's hard drive fails to mount.
CleanMyMac X - Clean, protect and speed up your Mac
Disk Drill by Cleverfiles - Recover any type of deleted files in Windows & Mac including Office documents, messages, and media files quickly and easily.
MacFly Pro - Smart assistant for better Mac performance