This prevents access on tablets, but allows the new density buckets (xxhdpi and xxxhdpi) and avoids errors on projects that are compiled against lower SDKs. It should be a direct child of the <manifest>
element in AndroidManifest.xml
<compatible-screens>
<!-- all small size screens -->
<screen android:screenSize="small" android:screenDensity="ldpi" />
<screen android:screenSize="small" android:screenDensity="mdpi" />
<screen android:screenSize="small" android:screenDensity="hdpi" />
<screen android:screenSize="small" android:screenDensity="xhdpi" />
<screen android:screenSize="small" android:screenDensity="480" />
<screen android:screenSize="small" android:screenDensity="640" />
<!-- all normal size screens -->
<screen android:screenSize="normal" android:screenDensity="ldpi" />
<screen android:screenSize="normal" android:screenDensity="mdpi" />
<screen android:screenSize="normal" android:screenDensity="hdpi" />
<screen android:screenSize="normal" android:screenDensity="xhdpi" />
<screen android:screenSize="normal" android:screenDensity="480" />
<screen android:screenSize="normal" android:screenDensity="560" />
<screen android:screenSize="normal" android:screenDensity="640" />
</compatible-screens>
Update 8.8.2016
Add this line if you want to support Nexus-5x-like devices with 420 density
<screen android:screenSize="normal" android:screenDensity="420" />