I just finished a theme called SimplyApp. It's a great theme for displaying your app. The modern style and very neat layout makes it easy to understand what you are trying to sell.
View the demo here: https://buildfaster.co/themes/simplyapp/
Get it here: https://gum.co/CbEkU
Use the promo code indie
to get 25% off the SimplyApp theme.
Let me know if I can help with the setup! 😄