Flat Theme Pro comes with few widgets along with some popular WordPress default widgets. You can access widgets from Dashboard > Appearance > Widgets.
Flat Pro About Us Widgets
You can add your about us at the bottom of your website using this widget. You can add title, image, about text, email id and phone number using this widget.
Flat Pro Blog Posts
Using this widget you can show your popular/ latest/ most commented blog posts. You can also determine the number of articles you want to show.
Flat Pro Image Ads
If you want to include image ads to your site, you can do so using this widget, you just need to add image link and upload the image.
Flat Pro Social Share Widgets
Using this widget you will be able to link the social profiles of your site which includes popular sites like Facebook, Twitter, Google Plus, Linkedin, RSS, Instagram, Dribble.
You can edit any of the widgets from the frontend (while in customization mode) simply by a shift-click on your desired widget.