This is a fascinating look at early prototype/bleed edge UX from Apple's first foray into tablet computing in 1991. It culminated in the limited released and then cancelled Apple PenLite device. Most interesting to me was Alan Kay's suggestion to use Kalman filtering to help make the pen motion feel smoother by denoising and predicting the motion. Turns out they used it on the first trackpads too. I never thought of using a Kalman filter for that sort of application. Maybe they still do. #apple #history #ComputerHistory #math
Apple PenLite: The iPad Before the iPad!