I really dislike the default textarea field, so I went looking for alternatives.
I found one called "BetterTextArea" that displayed a larger text field in a modal, but found that a bit wonky. http://colinramsay.co.uk/diary/2012/...encha-touch-2/
I took that code and modified it to display fullscreen when you tap to edit the textfield, which feels better on the phone and my tablet.
Here's the result of my work if anyone cares: https://gist.github.com/3703512