Smartphone App running on Tablet
check your AndroidManifest.xml and see if you have below prezented:

    &lt;supports-screens
        android:anyDensity="true"
        android:largeScreens="true"
        android:normalScreens="true"
        android:smallScreens="true" &gt;
    &lt;/supports-screens&gt;


There is no button for tablets :) you have to make it available for that type of screen.
Hope this helps.