Allows adjustment of space between keys

A free, open-source multi-purpose on-screen keyboard. It was designed with the needs of handicapped persons in mind. 

A free and open source assistive on-screen keyboard that runs on Windows.

iPad is a tablet device from Apple with built-in assistive features to complement your vision, hearing, motor skills, learning, and literacy.

An on-screen keyboard that enables people with physical disabilities to access any application within Microsoft Windows 95/ 98/Me/NT4/00/XP. 

Customizable access software specifically designed to work with the wireless IntelliSwitch or with IntelliKeys USB for scanning access. Use it with TrackerPro for on-screen keyboard access.

A predictive text-entry system with speech output for severely disabled people that has a restricted on-screen keyboard with an ambiguous layout. The main reason for using such a keyboard layout is that it enables the use of an eye tracker with a low spatial resolution.