If you no longer want an app to be available for download in the iTunes App Store, you can remove it from sale right through your iTunes Connect account.
This article provides a step-by-step guide to achieve this.
- Log in to your iTunes Connect account.
- Click the Apps icon.
- Select the app you would like to remove.
- Click the Pricing and Availability tab on the far left.
- Under Availability, select the option Remove from sale, then click the Save button at the top right.
- Return to the Apps section by clicking the navigation button at the top left.
- Locate your app once more, and you will see the status has changed to Developer Removed From Sale.
Within 24 hours (though usually less) your app will no longer appear in the App Store.