The Notes Menu
After clicking "Notes" at the bottom of the main menu, you'll be taken to a pane for viewing all of your previous notes. From here you can flick up or down OR use fast scrolling along the right side of the screen.
Click on any single note and you'll be shown the title and full text/images of your note. There isn't an enormous amount of formatting available in Evernote in general, so the mobile version is pretty similar to what you would normally see on the web or desktop clients. If you want all the extra tagging and such associated with your note, simply click "Details" for a screen listing the notebook, last date updated, creation date, and any tags or URLs.
To edit your note you'll need to click the pencil icon in the bottom right-hand corner. This will bring up an editor screen where you can change most of the fields. Sometimes a complex note will have certain values (like images) that cannot be changed on the mobile app, but you always have the opportunity to append text to the end of the note.
Lastly, if you would like to attach a note to an email or delete a note, those buttons are available at the bottom of the note page.
Back on the main notes menu, keep in mind that Evernote's powerful search is fully available on the app. Simply click the search box to begin a simple search or select "Advanced Search" for options to narrow by notebook, tags, geolocation, and date. If you'd like to look through your notes purely by geolocation, click the icon in the upper-left corner to see a map view with flags for each note.