We intentionally provide you with rising sign content because it's your rising sign that determines the areas of your life that the current astrology is impacting. (Most horoscopes are in fact written for the rising sign.) In other words, rising sign is the primary content. Sun is secondary. Your moon is tertiary.
However, we've heard from a number of customers that they would like access to their sun sign content as well, and we are working on adding this in future versions of the app.