1. Remove your app from the Google Play Store
1. Log in to your Google Play account: http://play.google.com/apps/publish/signup/
2. Click on the app you want to unpublish
3. Click on the "unpublish"
4. Answer to the question "Do you really want to unpublish this application?"
2. Remove your app from the App store
1. Log in to iTunes connect service with your iOS developer account : https://itunesconnect.apple.com
2. Click on the Manage Apps icon
3. Click on the app you want to unpublish
4. Click on the Pricing and Availability
5. Select "Remove from sale" option below "Availability"