It seems that flex is not working on textarea even if the parent container is set to vbox. It is defined on the textarea docs but I couldn't get it to work. The textarea component div container does work with flex but the actual textarea element does not adjust.
Also, scroll is not working on the textarea. If you test bare textarea element, it supports scrolling. I have tested this on the iPad.
Are these cases true for the current version of Sencha Touch textarea?