To implement Google Maps API in an Android application, we can follow the below steps:
Step 1:
Get Google Maps API key
To use the Google Maps API in our Android application, we first need to get an API key from the Google Cloud Platform Console. After getting the API key, we can enable the Google Maps Android API by enabling it in the Google Cloud Platform Console.
Step 2:
Add Google Play services dependencies
To utilize the Google Maps API in the application, we need to add the Google Play services dependencies to the project. We can do this by adding the following dependency line to the build.gradle file of the application:

dependencies {
	implementation 'com.google.android.gms:play-services-maps:17.0.1'}

Step 3:
Add MapFragment to the Layout File
To show the Google Maps in an Android application, we need to add a MapFragment to the Layout file. The MapFragment displays the Google Maps and needs to be added to the activity layout file. We can add the MapFragment to the layout file by adding the following code snippet:

<
fragment  android:id="@+id/mapFragment"  android:name="com.google.android.gms.maps.SupportMapFragment"  android:layout_width="match_parent"  android:layout_height="match_parent" />

Step 4:
Initialize the Google Maps API
To initialize the Google Maps API, we need to create an instance of GoogleMap and set it to the MapFragment. We can do this by using the following code snippet:

SupportMapFragment mapFragment = (SupportMapFragment) getSupportFragmentManager().findFragmentById(R.id.mapFragment);
mapFragment.getMapAsync(this);

Step 5:
Use Google Maps API functionalities
The Google Maps API provides various functionalities such as displaying maps, adding markers, drawing polylines and polygons, etc. To implement these functionalities in the application, we need to use the GoogleMap object. Some of the most commonly used functionalities are:- Showing a location on the map:

LatLng sydney = new LatLng(-33.852, 151.211);
googleMap.addMarker(new MarkerOptions().position(sydney).title("Marker in Sydney"));
googleMap.moveCamera(CameraUpdateFactory.newLatLng(sydney));

- Adding a marker:

LatLng sydney = new LatLng(-33.852, 151.211);
googleMap.addMarker(new MarkerOptions().position(sydney).title("Marker in Sydney"));

- Drawing a polyline:

PolylineOptions options = new PolylineOptions();
options.add(new LatLng(37.35, -122.0));
options.add(new LatLng(37.45, -122.0));
options.add(new LatLng(37.45, -122.2));
options.add(new LatLng(37.35, -122.2));
options.add(new LatLng(37.35, -122.0));
googleMap.addPolyline(options);

While developing this feature, we need to keep some key considerations in mind, such as:- Use of appropriate permissions to access the device location- Usage of Google Developers Documentation to stay updated with latest features and functionalities- Testing the app on different versions of Android OS for consistency- Limiting unnecessary use of Google Maps API to enhance app performance.Google Maps API is a robust set of tools that can help an Android developer create engaging maps, routes, and other location-based features. By following the above-mentioned steps and keeping these key considerations in mind, an Android developer can integrate Google Maps API successfully in their application.Citations:- Google Maps Platform Documentation- Starting Android development with Maps SDK for Android- Google Maps Platform Documentation- Maps SDK for Android- Android Developer Documentation- Fragments