I have a quick question regarding app icons. My question is are the icons that are displayed in the play store (the icons you see or click to go to the description of the app before you download) different then the app icons that appear on my home screen after I download and install the app? Or can the two icons, Play Store icon and phone (after download and installation) icon be different? So basically what I'm asking is can the developer use two different icon images, one for Play Store and one as the app image that appears on my phone after I have downloaded and installed the app?
They're different. The app's icon on the device is a drawable or mipmap resource which comes from the app's APK file. The app can have several icons for different situations too: icons can be different for different screen sizes and densities. This is needed to avoid the blurriness you'd get displaying a high-res icon on a low-res screen. In addition, since one app can have multiple activities, they can all have different icons. The icon that shows in the app drawer for each activity doesn't have to be the same as the icon that shows at the top of the activity when it's running. And the icon that represents the whole app in the system's app settings doesn't have to be the same as any of the other icons.
The icon that shows up on the Play Store (whether in the app or on the website) is uploaded by the app developer when they add the app listing. It's a higher-res image, so that it still looks good when displayed at a large size on the website. It doesn't come from the APK at all, so it can be a completely different image.
- Icons are also provided by your icon theme. But for convenience both kept nearly similar.
- Yes, it is possible to keep two different icons. But, that will create confusion to your user. I can cite you an example of an app. This app is SuperSu. It can change up to 7 icons ( including 1 invisible ) if a user opts.
- You can also change app icons by using some app that replaces icon from the app and from your system. For an example see this app.
- You can also follow this tutorial to change the icon.