Unfortunately, AppShed currently doesn’t support such functionality. Instead, you could create a link and put in the URL of the app in App Store or Google Play. This way the user will see the app and will be able to download it (if necessary).
Tags: Advanced Editing, Can I create a link in the app which will link to another app? I’d like it open that app once I click on the link, Creating Apps, Editing, Linking to another app