How To Show All Custom Post Types In A Category Instead Of Pagination?

Update your code as below.

// show all active coupons for this store and setup pagination
 query_posts( array(
              'post_type' => APP_POST_TYPE,
              'post_status' => 'publish',
               APP_TAX_STORE => $term->slug,
              'ignore_sticky_posts' => 1,
              'posts_per_page'=>-1
              ) 
           );