traccar-client-android/app/src/main/res/mipmap-anydpi-v26/ic_start_round.xml

<?xml version="1.0" encoding="utf-8"?>
<adaptive-icon xmlns:android="http://schemas.android.com/apk/res/android">
    <background android:drawable="@color/white"/>
    <foreground android:drawable="@mipmap/ic_start_foreground"/>
</adaptive-icon>