Question

My project is supporting a single apk for both phones and 10 inch tablets. However the UI for phones and Tablets are very different. I am releasing the app next week and I want the app to be available to phone users only for the time being. The tablet version is put on hold as testing is not completed.
Will the below declaration in manifest prevent applications from being installed/visible on 10 inch tablets

<manifest ... >
    <supports-screens android:smallScreens="true"
                      android:normalScreens="true"
                      android:largeScreens="true"
                      android:xlargeScreens="false"/>
    ...
    <application ... >
        ...
    </application>
</manifest>

The solution to this should be:This will filter out app from 10 inch(xLarge) tablets?

<manifest ... >
<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" />
    <!-- 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" />
    <!-- all large size screens -->
    <screen android:screenSize="large" android:screenDensity="ldpi" />
    <screen android:screenSize="large" android:screenDensity="mdpi" />
    <screen android:screenSize="large" android:screenDensity="hdpi" />
    <screen android:screenSize="large" android:screenDensity="xhdpi" />
</compatible-screens>
...
<application ... >
    ...
<application>

Answer 1

Will the below declaration in manifest prevent applications from being installed/visible on 10 inch tablets

No. With that manifest entry, you are telling Android to allow your app on -xlarge devices, with Android doing some extra work to try to make your UI stretch to fill the screen.

To block installation (and be filtered out of the Play Store listings), you will need to use <compatible-screens>.