This is an app for visualising and generating images of keyboard layouts and designs. The app allows you to configure and render images of a keyboard layout which can be be saved on the device's SD Card. Various common layouts and physical keyboard designs are built-in, but you can also edit existing ones and add your own.
It's what I have been using to generate my keyboard layout images for several years now, such as the ones on the Colemak-DH site, but now I have open sourced it and made it publicly available on Google Play.
Using Colemak-DH with Seniply.