Header
At this time iStore theme comes with 3 styles of header. You can activate whichever you think suits the most on your WooCommerce store. 
Sticky Header
Turning this option ON will enable the browser scrolling to show sticky header on top of the page. So the sticky logo and menu will be displayed on top of the browser while the visitor scrolls through the page. You will find this option under Theme Options, Header.
Subheader
The theme has a subheader area which adds title of the page/post/product and breadcrumb on the right side. This is part of the on page SEO practices.
- Enable Subheader – Turn subheader On or Off.
- Show Page Title – This allows you to show or hide title. If you hide page title here, the post/product/page title will be displayed under the post body on top of the content.
- Show Breadcrumb – Show or hide breadcrumb. it is good for SEO purpose to display breadcrumb. However you can still hide it if you decide to do so.
- Background image – This allows you to set background image specifically for the subheader area. So it looks different if you want it to. You can also setup specific background color for the subheader if you do not want to display a background image. Head to Theme Options, Colors, Header. Look for Subheader heading and change color for the background.
Action Bar
Action bar is displayed on the very top of the web page. 
Enabling action bar gives you additional options to configure on your WooCommerce store.
- Enable Action Bar – Turn action bar On or Off
- Text – The text which is displayed in the middle of the action bar ie; center aligned. It also accepts the following HTML tags for display. <a href> <strong> <em>
- Phone Number & Email Address
- Social sharing – Enable displaying social icons. The icons will be displayed on top right in action bar