The newly revealed Phorm case for the iPad mini will create disappearing physical key-hump things over the tablet's touchscreen keyboard, and in theory offer what the developers at Tactus hope is a better typing experience.
Phorm is a two part case, with one part that goes on the back and wraps around the sides, and the other part which is a transparent screen that goes on top of the tablet's display. The screen contains microfluidic channels that are activated when a slider is moved on the back of the case. The transparent keys on the screen then rise up on top of the virtual keyboard.
The Phorm case is currently available for $99 during its pre-order period, but the price will go up to $149 when it launches sometime in the summer of 2015. This case is obviously not compatible with any third party keyboard for the tablet, and could become useless if Apple decides to change the virtual keyboard or if you prefer to type sideways. There are plans to launch a similar case for the iPhone 6 Plus and the iPad Air in the future.