Divi makes it easy to customize your website with drag & drop. There are plenty of child themes and extensions that let you do more with it. Smart Apps is a responsive website layout with customizable color, font, and other features. As the name suggests, this modern layout lets you build a professional presence for your app.
Smart Apps has predesigned sections, so you can go live faster. It comes with testimonials, pricing tables, and other common elements you would expect an app landing page to offer. themeix is the designer behind this theme. You can find out more about it here.