A best practice is to use a single app store link that can detect if the consumer is clicking from an iOS or Android device and then routes that user to the correct app store. These icons provide a familiar experience on websites but separate links can be inefficient especially when scaling campaigns on smaller screens and ad formats. Traditional web URLs require separate app store links for the Google Play and Apple App Stores.
When developing a strategy, keep in mind that not all app download links are created equal.
As a mobile app marketer you need to get more app downloads and the way to do that is by promoting an app store link.