ThickButtons is a replacement soft-keyboard for Android phones that works in a very unique way. It uses the predictive word functionality available in many soft keyboards (where it can predict what word you are likely to be typing based on what you’ve typed) but takes that one step further by enlarging the next letter on the keyboard. Take a look:
This seems very ingenious but the constantly changing key sizes could be frustrating because it interferes with our ability to use consistent elements of the environment in learning. When the mappings between stimulus (key size, location) and response remain fixed (as in a hardware or soft-keyboard), it is much easier for us to learn and automatize. This is one of the seminal findings of cognitive psychology/human factors research. In training, reaching automaticity means reaching the state where very little attention is required–in this case, attention to where the button is located on the keyboard. That is how, with extensive practice, some people can become extremely quick soft keyboard typists.
Consistently mapped situations, where the keys remain in the same position, in the same size, encourage automaticity (more or less) while variably-mapped situations discourage automaticity (performance is “controlled”). When automaticity is reached, performance feels effortless and automatic (think of tying your shoe). However, in VM situations, performance never reaches automaticity and always feels very effortful.
I wonder if the purported benefits of this configuration outweigh the possible variably-mapped fiasco…it’s an empirical question! (i.e., someone should do a study).
For more on the CM/VM and automatic/controlled processing in attention, please see this Google Scholar link to just some of the relevant papers. Note that some of them are quite technical and may require a background in cognitive psychology.