Ron Rennick

Uses a custom post type to allow editing of the promotion(s). The most recent published promotion post by date is shown below single posts.
Some (CSS tips)http://wpebooks.com/free-plugins/genesis-promotion-box/ for your child theme.
Requires the Genesis Theme Framework.

Genesis Promotion Box

This plugin allows you to add a promotion box after a single post in Genesis.

omnishop

With our seamless integration, your website becomes an invaluable platform to promote your mobile app like never before. 
Imagine having a direct channel to engage with your website visitors and effortlessly convert them into loyal app users. 
It’s time to tap into the immense potential of your existing web traffic and turn it into a powerful source of app growth.
Promoting Apps with Smart App Banners is something both Apple iOS and Android systems support and by using our plugin, we allow you to access that functionality with ease.
For iOS: 
* Simply input the application ID
For Android: 
* Several options to set how you want your app banner to look

Promote mobile app on website

Promote your mobile app on website. Use a mobile banner to offer users to install your app. Easy and free.

Genesis Promotion Box vs Promote mobile app on website