Like all of your marketing, make sure that your YouTube video has a clear call to action. Videos related to your app should always ask the user to download the app. For more advanced walkthroughs and tips which are more geared to exisitng users you may wish to include a call to action asking them to rate, review and share the app with their networks.
Every Tuesday App Promo will be providing tips on app marketing and promoting applications based on their experience leading marketing campaigns for applications across platform. These tips are like regular marketing vitamins aimed to boost discovery and visibility for app publishers to better succeed in the business of their apps.