zOutline

A straightforward, uncomplicated outline editor.
You tap an item to select.
You double-tap to edit an item.
You swipe left on an item to delete an item..
Or you tap-and-hold to cut & paste, etc.
Multiple outlines can be edited at once in different tabs.
zOutline remembers what you were editing even if you kill the app.
You can send outline files as email attachments, and open outline file attachments. zOutline permits export as HTML, RTF or text.
Outline items can be enumerated or dotted.
Items can be bold, italic, underlined.
Several fonts and text colors are available.