MessageSlate

The MessageSlate was a large tablet computer that was prototyped by Apple Computer for its Newton mobile platform.

History
The MessageSlate (codenamed Senior) was planned to be the largest of 3 versions of mobile devices running Newton OS. Apple applied for the "MessageSlate" trademark on April 5, 1993. Industrial designers Marc van de Loo, John Tang, and David Lima developed prototype units between March and August 1993. The resulting large design resembled the Mac OS-based PenLite prototype. However, only the smallest version (codenamed Junior) was shipped as the first MessagePad on August 3, 1993.

Articles

 * Apple Newton prototype ‘MessageSlate’ by Jeremy Barr-Hyde at JB Retro Collect (2015-08-10)
 * The 'iSlate' - Reviving an Old Name? by Arnold Kim at MacRumors (2009-12-18)