Note: When removing your app from a public app store it often takes some time before the app is removed by the app store.
Anyone that has the app can continue using the app, you cannot remove an app from a user’s device once they have installed the app.
Apple App Store
From the guide here: https://help.apple.com/app-store-connect/#/dev7013b314c
- From the homepage, click My Apps, select the app, then in the left column, select Pricing and Availability.
- On the right, below Availability, select Remove from sale.
- In the upper-right corner, click Save.
- Login to Goole Play Console.
- In the application list on the main page, click the app you want to unpublish
- From the left menu click Store Presence – Pricing & Distribution
- Click on Unpublish and then Submit Update at the bottom