AmigaOS 4, (abbreviated as
OS4 or
AOS4), is a line of
Amiga operating systems which runs on
PowerPC microprocessors. It is mainly based on AmigaOS 3.1
source code developed by
Commodore, and partially on version 3.9 developed by
Haage & Partner. "The Final Update" (for OS version 4.0) was released on 24 December 2006 (originally released in April 2004) after five years of development by the Belgian company
Hyperion Entertainment under license from
Amiga, Inc. for AmigaOne registered users.