主要会去使用PackageManager这个类

 public void getAppNames(){
        PackageManager pm = this.getPackageManager();
        List<PackageInfo> infoList =pm.getInstalledPackages(0);
        int listSize = infoList.size();
        for(int i=0;i<listSize;i++){
            Log.d("Appnames", infoList.get(i).toString());
        }
    }
}

其实还需要去判断是否是 系统应用 如何判断系统应用呢：

 public void getAppNames(){
        PackageManager pm = this.getPackageManager();
        List<PackageInfo> infoList =pm.getInstalledPackages(0);
        for(PackageInfo packageInfo:infoList) {
//加入一个这个判断          
  if ((packageInfo.applicationInfo.flags & ApplicationInfo.FLAG_SYSTEM) == 0) {
                Log.d("Appnames", packageInfo.packageName.toString());
            }
        }
    }