Hotentorで作ったIntentユーティリティから抜粋。

IntentUtil.java

package jp.hateblo.shin.hotentor.util;

import android.content.ActivityNotFoundException;
import android.content.Context;
import android.content.Intent;
import android.content.pm.PackageManager;
import android.net.Uri;

import jp.hateblo.shin.hotentor.App;

/**
 * Created by shin on 2014/08/31.
 */
public class IntentUtil {

    public static boolean isAppInstalled(String appId) {
        try {
            App.getAppContext().getPackageManager()
                    .getApplicationInfo(appId, PackageManager.GET_META_DATA);
            return true;
        } catch (PackageManager.NameNotFoundException e) {
            return false;
        }
    }

    public static void sendIntentWithUrl(Context activity, String url) {
        Intent intent = new Intent(Intent.ACTION_VIEW, Uri.parse(url));
        activity.startActivity(intent);
    }

}