Util for using MapView instead of MapFragment and still avoid boilerplate code to delegate all the activity lifecycle (onCreate, onResume, onPause, onDestroy, etc...) to the MapView.

MapsUtils.java

import android.app.Activity;
import android.app.Application;
import android.os.Bundle;
import com.google.android.gms.maps.MapView;
import com.google.android.gms.maps.MapsInitializer;

import static java.lang.String.format;

public class MapsUtils {

    /**
     * Allows you to use google maps view (not fragment) without the hassle of
     * delegating all the activity lifecycle events to it.
     * <p>
     * **IMPORTANT** You MUST call this in your activity onCreate() method.
     */
    public static void delegateLifecycle(Activity targetActivity, Bundle savedInstanceState, MapView mapView) {

        // Make sure the application implements LowMemoryListenableApplication
        if (!(targetActivity.getApplication() instanceof LowMemoryListenableApplication)) {
            throw new IllegalArgumentException(format("%s must implement LowMemoryListenableApplication delegateLifecycle() to work.",
                    targetActivity.getApplication().getClass().getCanonicalName()));
        }

        // Call maps first callbacks
        MapsInitializer.initialize(targetActivity);
        mapView.onCreate(savedInstanceState);

        // Listen for LowMemory on application
        LowMemoryListenableApplication application = (LowMemoryListenableApplication) targetActivity.getApplication();
        OnLowMemoryListener lowMemoryObserver = mapView::onLowMemory;
        application.registerLowMemoryObservable(lowMemoryObserver);

        // Register an activity lifecycle callback that redirect each lifecycle event to maps
        targetActivity.getApplication().registerActivityLifecycleCallbacks(new Application.ActivityLifecycleCallbacks() {
            @Override
            public void onActivityCreated(Activity activity, Bundle savedInstanceState) { }

            @Override
            public void onActivityStarted(Activity activity) { }

            @Override
            public void onActivityResumed(Activity activity) {
                if (activity == targetActivity)
                    mapView.onResume();
            }

            @Override
            public void onActivityPaused(Activity activity) {
                if (activity == targetActivity)
                    mapView.onPause();
            }

            @Override
            public void onActivityStopped(Activity activity) { }

            @Override
            public void onActivitySaveInstanceState(Activity activity, Bundle outState) {
                if (activity == targetActivity)
                    mapView.onSaveInstanceState(outState);
            }

            @Override
            public void onActivityDestroyed(Activity activity) {
                if (activity == targetActivity) {
                    application.unregisterLowMemoryObservable(lowMemoryObserver);
                    targetActivity.getApplication().unregisterActivityLifecycleCallbacks(this);
                    mapView.onDestroy();
                }
            }
        });
    }

    /**
     * By implementing this method you must provide a way to listen to
     * onLowMemory events in this application.
     */
    public static interface LowMemoryListenableApplication {
        void registerLowMemoryObservable(OnLowMemoryListener observable);

        void unregisterLowMemoryObservable(OnLowMemoryListener observable);
    }

    public static interface OnLowMemoryListener {
        void onLowMemory();
    }
}