Google Play Featured-Image Guidelines | Android Developers Blog
If your app is selected for featuring on Google Play,our editorial team uses your 1024 x 500 “Featured Image” to promote the app on tablets, phones, and the Web. The image can be used on the home page on all versions of Google Play (Web, tablet and phone), on your product page in the Web and tablet versions, and on current and future top-level Google Play pages on phones.
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