Splashtop Remote – Free for Samsung.
Review on Windows – Easy and simple installation. Great connectivity. No serious lag when used with Paint.
Review on Mac – Easy and simple installation. Great connectivity. A bit laggy though.
Splashtop Extender – Free trial for 5min only.
Astropad for Mac $29.99 ipad, Edu Ver SG29 – purpose-built to be Wacom by ex-Apple engineer. iPad is free.
Air Display 3 (supersedes Air Stylus) for Mac $14.99 ipad, $10.40 Galaxy