I tried making the small icon exactly 16x16, gray-scaled, nothing but gray and white (the gray color being
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First let’s understand the Android documentation which is as follows
“Update or remove assets that involve color. The system ignores all non-alpha channels in action icons and in the main notification icon. You should assume that these icons will be alpha-only. The system draws notification icons in white and action icons in dark gray.”
Now this is easy to miss and I have seen many apps that are live in the app store with thousands of users who haven’t followed the mentioned guidelines.
So let me explain in detail how you can convert your notification icon to an Android friendly one with a few clicks.
In your favourite image editor open up your icon file. Convert all parts of the image that you don’t want to show to transparent pixels. All colors and non transparent pixels are displayed in white. Let us go through an example.
You can ask designer or use this tool to generate your icon