Get the smallestWidth property in density pixels for the current device. >= 600 dp is a 7' tablet, >= 720 dp is a 10' tablet.

DensityCalculator.java

public int getSmallestWidthDensity(Activity context) {
    DisplayMetrics metrics = new DisplayMetrics();
    context.getWindowManager().getDefaultDisplay().getMetrics(metrics);

    int widthPixels = metrics.widthPixels;
    int heightPixels = metrics.heightPixels;
    float scaleFactor = metrics.density;

    float widthDp = widthPixels / scaleFactor;
    float heightDp = heightPixels / scaleFactor;

    return (int) Math.min(widthDp, heightDp);
}