I tend to use my iPad more to consume content than to produce it. So, my main use case for buying Textastic was as a slick tool for reviewing code -- either as part of a formal code review or to gain an understanding of some third party component. In both of these cases, it would be nice to be able to annotate the code with my comments as I review.
I click on a line number and a dialog pops up to input a comment. Once I made a comment, there would be some sort of visual indicator telling me that there was a comment at that spot. Finally, when I was done my review session, I'd be able to collect my comments in some form. This could be as simple as creating a text file FileUnderReview.rb.comments with entries like:
Line 34: Some insightful comment.
(Or it could use a standardized file format instead if there is anything out there)
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