IPhone reference App

I would like an iPhone app designed which is a basically a list of articles with information. These articles will need to be categorised and sub-categorised. Essentially it is going to be a reference tool.

The articles will feature structured text with various headings and section content (This will all be provided by me). There would need to be backwards navigation along the top as well as a title for the article.

It is very important that it needs to be searchable.

I have had an idea for this app for a long time but someone has beaten me to a basic version of it, however I think it can be done better and offered cheaper on the App store.

Depending on the Apps success there is potential for Android and Blackberry versions too. So someone with knowledge of all three platforms would be ideal, but this is by no means a necessity.

The attached word document gives a more detailed brief for what I want from the App with links to a similar one and one that I like how it is designed.