If you are on the latest Android app (version 6 or greater), you can customize the menu items that expand from the left side of the app. You can create up to 10 custom links that you can target to open up within the app. The links will then display in the slide-out menu.
You can target links to your other websites, sponsor websites, promo or contest pages, or any other websites you would like your listeners to visit. And the good thing about this is that it opens up the webpage within the app, so your listeners don't have to leave your app.
You can create the links in your Radio Control Panel, under the MOBILE APPS section. The links will be added instantly. You will just need to close the app and open it again to see the updated links.