[3] PenPoint OS ran on a number of Intel x86-powered tablet PCs from IBM (the first use of the "ThinkPad" brand name),[4] NCR,[5] and others, and on AT&T's EO Personal Communicator.

The company enjoyed high levels of public awareness and generally positive attention from industry press, but it ran into fierce competition, first from Microsoft (whose Pen Services for Windows were later the subject of an FTC investigation and patent violation suits by GO), and later from Apple's Newton project, and others.

This sale raised much-needed cash but introduced new problems, as EO then ceased to coordinate well with GO's management, even considering adopting competing operating systems.

[6] The loss of AT&T's support left GO with little chance of future revenue and, after burning through $75 million of venture funding, the company closed in July 1994.

[7][8] In a separate legal matter, in April 2008 certain features of the Microsoft's Windows/Tablet PC operating system and hardware were found to infringe on a patent by GO Corporation concerning user interfaces for pen computers.