To provide a counterexample, I definitely type less than 50 (their median) wpm on a mobile device. More like 10 - especially if there are symbols involved that

To provide a counterexample, I definitely type less than 50 (their median) wpm on a mobile device. More like 10 - especially if there are symbols involved that are not on the first two screens. On blackberry maybe 50. On the other hand, speech is a lot worse. A lot of times you can't afford to have 10%, 5% or even 1% error rate since messages are usually short and you cannot infer intended meaning easily. So my WPM accounting for correcting speech with swype is <10.