Though Activity_step5 is Launcher,how ChronoActivity1 is Launching First?

[brajabasi]

            <category android:name="android.intent.category.LAUNCHER" />
        </intent-filter>
    </activity>

[aa-ndrej]

Activity_step5 is launched when you open the app from your phone. However in Android Studio you can set different Launch Options for different Run Configurations. When you click on Run > Edit Configurations... you can see, that for Step 1 ChronoActivity1 is set as the launch activity.

If you want to start Activity_step5 from Android Studio you can for example run the Step 5 - Sharing VMs solution configuration.