AnkiApp gives you powerful features for creating cards. The screenshot below highlights the important parts of the card creation interface.
a) This is the "preview" of what your card will look like. It shows each field of the card outlined with a dashed line, with the field's name in the top-left corner.
b) This is the name of the field that you can edit using the tools immediately below this label.
c) This is the toolbar for this field, which lets you add images and sounds (sounds are desktop-only), and style the text of your cards.
d) This is the text area, where you can type in the things you want on your flash cards.