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startActivity does not create activity the second time

I have two applications installed on my device, application A and application B.
When a user launches application A, they press a button to launch application B.
I use the following code:
Intent intent = Global.CurrentContext.getPackageManager().getLaunchIntentForPackage("some.random.app");
Global.CurrentContext.startActivity(intent);
The first time the user does this, it works fine and works as expected, however, if the user then launches the phones task manager and swipes away application B. When the user then presses the button in application A. The activity is not created.
I believe this is something to do with the way that the task and the activity are being destroyed by android. My thought process is that when the user swipes to kill application B that the activity is destroyed, but the task remains. Then the second time they press the button in application A, that it's attaching to the old task and then not showing for the user.
Application A's activity manifest for the activity:
<activity
android:name="a.a.a.LogonActivity"
android:label="#string/app_name"
android:noHistory="true"
android:screenOrientation="portrait"
android:theme="#android:style/Theme.Light.NoTitleBar"
android:windowSoftInputMode="stateHidden"/>
Application B's activity manifest for the activity:
<activity
android:name=".activity.HomeActivity"
android:label="#string/app_name"
android:screenOrientation="portrait"
android:windowSoftInputMode="adjustPan">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>

When I set android:noHistory="false", it works. I think it is android:noHistory="true" killed applicationA's top activity, makes it doesn't work.

Up Navigation and singleTop launch mode

I have an activity A, and when I press an toolbar item, it starts activity B using startActivity(intent). Whenever I press back button or the up navigation icon, it closes my app. I believe it's because I'm using launchMode="singleTop" in my parent activity (I'm using this because I have a Search View and a searchable configuration, because I don't want to start another instance of my activity on for search). So the question is: How can I get back from child activity(B) to parent activity(A) using both up navigation and back button without closing my app? I've searched about it, and I found something about onNewIntent(). If this is my solution, how should I use it properly?
Here is my manifest file:
<activity
android:name="com.example.fernando.inspectionrover.MainActivity"
android:screenOrientation="landscape">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<action android:name="android.intent.action.SEARCH" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
<meta-data
android:name="android.app.searchable"
android:resource="#xml/searchable" />
</activity>
<activity
android:name="com.example.fernando.inspectionrover.BluetoothSettingsActivity"
android:parentActivityName="com.example.fernando.inspectionrover.MainActivity"
android:screenOrientation="landscape">
<meta-data
android:name="android.support.PARENT_ACTIVITY"
android:value="com.example.fernando.inspectionrover.MainActivity" />
Here is how start my new activity:
switch (id) {
case R.id.bluetoothActivity:
Intent switchActivity = new Intent(this, BluetoothSettingsActivity.class);
startActivity(switchActivity);
Log.i(LIFE_CYCLE, "Switching from " + getLocalClassName() + " to Bluetooth Setting Activity");
finish();
break;
}

Single Top means that if you launch an activity that is already on top, it wont be created again just resumed.
The reason your back navigation close the app is because you are calling finish() just after you start a new activity. Which means you don't need that activity anymore so it is removed from the stack. If you go back on activityB, the app will close because there is nothing to go back (you called finish() remember?

I may be just poking at the easiest answer but I think the main problem is that you are calling finish after you start the new activity. This calls on destroy for the calling activity and removes it from the activity stack.

Root Activity is getting called again and again when coming from background to foreground instead of last activity in stack

I am developing an hybrid app using IBM worklight where I have to open another webview on the top of existing webview(Cordova webview),so i created a new activity(WebView Activity) to load my external page,but when i am going to background from webview activity by pressing home button and again coming to foreground my MainActivity getting called and restarts the app,I have used singleTop for my MainActivity in manifest file
<activity android:name=".MainActivity"
android:label="#string/app_name"
android:configChanges="orientation|keyboardHidden|screenLayout|screenSize"
android:launchMode="singleTop"
>
<intent-filter>
<action android:name="android.intent.action.MAIN"/>
<category android:name="android.intent.category.LAUNCHER"/>
</intent-filter>
<intent-filter>
<action android:name="com.main.sample.NOTIFICATION"/>
<category android:name="android.intent.category.DEFAULT"/>
</intent-filter>
</activity>
<activity android:name=".WebViewActivity"
android:label="#string/app_name"
android:configChanges="orientation|keyboardHidden|screenLayout|screenSize"
android:launchMode="singleTop"
android:theme="#style/Theme.Transparent">
</activity>
I don't know why it is happening,I want my last activity to get resumed instead of main activity

Read documentation for the modes.This will explain you about what is happening:
"singleTask" and "singleInstance", should be used only when the > activity has an ACTION_MAIN and a CATEGORY_LAUNCHER filter. > Imagine, for example, what could happen if the filter is missing: An > intent launches a "singleTask" activity, initiating a new task, and > the user spends some time working in that task. The user then presses > the Home button. The task is now sent to the background and is not > visible. Now the user has no way to return to the task, because it is > not represented in the application launcher.
This is one potential solution.There are multiple ways to do this.
Try using the following code in the onCreate method of the activity that is specified as the Launcher Activity in the Manifest:
if ((getIntent().getFlags() & Intent.FLAG_ACTIVITY_BROUGHT_TO_FRONT) != 0) {
finish();
return;
}
This will finish your Launcher Activity before it is displayed by detecting that there is already a task running, and your app should instead resume to the last visible Activity.

Android main activity does not launch on start

The main activity does not launch when I open the application; I close it by clicking on the home button. When the app starts, it opens on the same page where I was when I clicked the home button. It somehow remembers the last page I was at, and opens that page instead of the launcher activity. I added onDestroy() to onPause() on all the activities, but that didn't help either.
I am not sure what code to add here, so I'm attaching my AndroidManifest. Thanks! Below are the three activities in the AndroidManifest.
<activity android:name="example.Activity1" android:label="MyApp"
android:configChanges="orientation" android:screenOrientation="portrait">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity
android:name="example.Activity2"
android:configChanges="orientation"
android:screenOrientation="portrait" >
</activity>
<activity
android:name="example.Activity3"
android:configChanges="orientation"
android:screenOrientation="portrait" >
</activity>

When Home button is pressed, onStop method is called in your activity. So what you may do is to add finish(); in onStop method to destroy your activity.

Your activity is saved on the backstack. Play with the flags passed to the intent when you create your activity. For example, FLAG_ACTIVITY_CLEAR_WHEN_TASK_RESET will clear all the activities from this to up the backstack.
Intent myIntent = new Intent(this, MyActivity.class);
myIntent.setFlags(Intent.FLAG_ACTIVITY_CLEAR_WHEN_TASK_RESET);
startActivity(myintent);
When you close, o exit myintent Activity, when you reopen you app it will clear delete myintent Activity from the backstack and all the activities opened from this activity.

Make sure you activity name includes you entire package name instead of example.
Or just replace android:name="example.Activity1" with android:name=".Activity1"

Android launchMode="singleTask" and Intent-filters

So I have an Activity A that is defined in the AndroidManifest.xml as defined below:
<activity
android:name=".activity.A"
android:screenOrientation="landscape"
android:windowSoftInputMode="stateAlwaysHidden"
android:launchMode="singleTask">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
This Activity launches a welcome Screen which we will call Activity B.
If you launch the application the Welcome screen is displayed and then once the user is done with it Activity A comes back.
The issue I am having is when I push the "Home" button from the welcome screen I go back to the Home Screen as expected. Now when I reclick on the Application Icon the application won't launch. Instead both my Activity A & B get destroyed. If I click on the icon again then the application relaunches as expected.
Now if I'm on the welcome screen and push the back arrow and reclick on the App icon it launches the application as expected. I don't have to push it twice.
Unfortunately I have to use the launchMode="singleTask" since it is a requirement for integration with another team. I have read the Android API's for Tasks and Back Stacks numerous times. Any pointers or suggestions would be greatly appreciated.
I came across a blog indicating there is an undocumented bug with using singleTask and intent-filters together but didn't find any official documentation on this.
Thanks
EDIT
Launching Activity B like this:
Intent intent = new Intent(context, B.class);
startActivityForResult(intent, CONST_VAR);

I tried making two activities which launches ActivityB from Activity A. I see no such problem as described in the question. PFB my manifest. Also, when you say home button, is it Phone home button or your app specific home button. PFB my manifest
<activity
android:name="com.android.testsingletask.MainActivity"
android:launchMode="singleTask"
android:screenOrientation="landscape"
android:windowSoftInputMode="stateAlwaysHidden"
android:label="#string/app_name" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity
android:name="com.android.testsingletask.WelcomeActivity"
android:screenOrientation="landscape"
android:windowSoftInputMode="stateAlwaysHidden"
android:label="#string/app_name" >
</activity>