I've realized that for my mobile phone the typing speed will just never be great regardless of the input method. Tools like this (and SwiftKey) improve that a bit but not to a life-changing degree.
For the desktop this might be quite amazing however since, unless you're a perfect touch typist, you will always make a small number of mistakes.
These small mistakes can be caught fairly easily (especially given the much larger training set you'll gather on a desktop) and since you're looking at the screen anyhow it's fairly easy to detect damn-you-autocorrect mistakes before they slip through.
TL;DR; Don't use this to make inherently slow data entry a bit faster; use it to make fast data entry even faster.
Apple in Mac OS X has brought the same error correcting features that exist in iOS for typing to every single text box that is rendered and has a cursor placed in it. This has allowed me to type faster and even if I make mistakes the OS will correct them for me most of the time. It still needs a little bit more time and tuning, but so far it has proven to be absolutely fantastic when typing.
See Preferences -> Language and Text -> Correct Spelling Automatically.
> for my mobile phone the typing speed will just never be great regardless of the input method.
Actually, way back when PalmOS and PocketPC were all the rage, there was a company that released something called the Fitaly keyboard. I don't know what you qualify as "great" typing speed, but with this keyboard they advertise 50wpm with a stylus, I was able to achieve 60wpm after some practice.
The point is, it is definitely possible to achieve fast input speeds on mobile devices.
Admittedly it did take some practice and probably isn't great for the average consumer.
Also it seems like it's finally coming full circle around back to styli again. It seems like they're now being advertised as a new feature, which I think is kind of funny. Granted, they aren't using resistive screens anymore, so it is sort of new.
I'm waiting for a good stylus-enabled device before I purchase anything new. The fact that you can't draw on most of these tablets is silly.
Yeah, I wrote about this a while back, the stylus will always be useful for pretty fundamental reasons, though there will be phases in which it's not easy to implement (we're coming out of one right now):
http://techcrunch.com/2011/11/11/in-defense-of-the-stylus/
These systems usually use predictions (see Markov chains) based on your previous input to automatically catch and correct those small typos and prevent you from needing to skip two words back to fix the typo.
In the case of a false positive (correction where none was needed) you can just delete the entire word and type again.
As this is usually done using Markov chains which learn from your previous input this could even be used for programming.
in the case of a false positive you have to go back two words and correct it (in the idea the word was corrected automaticaly). I'm afraid this happens more than I make mistakes typing.
For the desktop this might be quite amazing however since, unless you're a perfect touch typist, you will always make a small number of mistakes.
These small mistakes can be caught fairly easily (especially given the much larger training set you'll gather on a desktop) and since you're looking at the screen anyhow it's fairly easy to detect damn-you-autocorrect mistakes before they slip through.
TL;DR; Don't use this to make inherently slow data entry a bit faster; use it to make fast data entry even faster.