40 and 80 Track DOS 1980 Sympathetic Software Apple II Desktop (v1.0) 1986 Version Soft Apple II Desktop (v1.1) 1986 Version Soft AmDOS (v3.5) 1986 Gary B. Little David-DOS 1982 David Data Diversi-DOS (v2.0c) 1982 Diversified Software Research Diversi-DOS (v4.1c) 1983 Diversified Software Research DOS 3.3 System Master (1980, alternate) 1980 Apple Computer, Inc. DOS 3.3 System Master (1980 version) 1980 Apple Computer, Inc. DOS 3.3 System Master (1983 version) 1983 Apple Computer, Inc. DOS Anatomy 1986 Windsor Scientific GEOS 1988 Berkeley Softworks ProDOS (v1.1.1) 1983 Apple Computer, Inc.