Geos
From Computer History Wiki
Geos started as a graphical environment for the Commodore 64, 128 and the apple II microcomputers.
8 bit versions
Version 1.x
Version 2.x
16 bit versions
Soon it was obvious that the 8bit market was dying, and it was time for Geos to transition to new platforms. A new system was written in assembler that used the motif look & feel to give the IBM PC a new GUI. AOL was an early adopter of Geos, and it's early dialer programs used Geos.
For a small ammount of time Geos was bundled with lower end systems, as it had a low system requirements. However their delays in giving out a developer SDK doomed the platform, as they were unable to compete with Microsoft Windows 3.0 & their onslaught.