Its something of a cliche to request Vi keybindings in an editor, but as someone who does most of his server-side development in Vim, having a client side editor with the same is helpful.
Textastic so far seems quick and easy to use, as I often just want a place to paste some code and make quick edits. Vi key bindings would eliminate some of the effort in context switching.
I am _not_ advocating Vim compatibility (macros, plugins), just movement and common ex commands (find, replace).
Customer support service by UserEcho