It's a vex of us all: we're reading our posts, need to change something, but how do we get to the administration? That's what Oceia bar is all about.
It's a peeve of us all: we're reading our posts, decide we want to add something new, but how do we get to the administration? In the default theme, there's a link, but we certainly don't all use that. That's what Oceia bar is for -- it provides quick, visible access to the admin for just to basic Dashboard, to editing a specific post, or adding a new one.
In fact you can basically try this out on WordPress.com if you have an account. (Oceia bar is based on the WordPress.com bar's functionality -- the bar WP.com uses is not distributed to the public.)