Purpose of using CATEGORY_HOME in android manifest?

What is the alternative to removing the following from AndroidManifest: ``` <activity android:name="com.apper.main.UserActivity" android:label="@string/app_name" android:launchMode="singleTask" android:clearTaskOnLaunch="true" android:stateNotNeeded="true" > <intent-filter> <action android:name="android.intent.action.MAIN" /> <category android:name="android.intent.category.HOME"/> <category android:name="android.intent.category.LAUNCHER" /> </intent-filter> </activity> ``` I also found that after removing the above line, there was no impact to my android application. What's the main use of this category and what's the alternative to it. If the intent of this category is to launch the home screen then it can be done by the following: ``` Intent homeIntent= new Intent(Intent.ACTION_MAIN); homeIntent.addCategory(Intent.CATEGORY_HOME); homeIntent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK); startActivity(homeIntent); ``` This above code will launch the home screen but why the line in the android manifest ? What's the purpose as removing the line from here does nothing change the application ?