There is nothing stopping you storing HTML in the database as the blog itself.
The important point is to not include any display specific code.
For display purposes consider using CSS to manipulate the HTML (and any images).
Have a look at Zen Garden to get a better idea of what I mean - CSS Zen Garden: The Beauty of CSS Design
Android has its own way of applying styles Styles and Themes | Android Developers
So perhaps store your blog as plain text or xml, convert to the appropriate format (HTML/android:text) and apply the appropriate style as required, when required.