Check out example codes for "google map set default zoom android studio". It will help you in understanding the concepts better.

Code Example 1

LatLng loc = new LatLng(33.8688, 151.2093);
mMap.addMarker(new MarkerOptions().position(loc).title("Sydney"));
mMap.animateCamera(CameraUpdateFactory.newLatLngZoom(loc, 18), 5000, null);

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