Angular 6 - @types/googlemaps/index.d.ts' is not a module

For Angular6~

1. npm install @types/googlemaps --save-dev or yarn add @types/googlemaps
2. Add "googlemaps" to tsconfig.app.json types array

3. Add "googlemaps" to tsconfig.spec.json types array

4. Add /// <reference types="@types/googlemaps" /> on the first line of your component.ts file. This line will import @types/googlemaps. (Line1 of example below)
5. Declare google variable as declare let google: any; (Line6 of example below)

Ref:

• https://stackoverflow.com/a/52200117/10009565

You probably don't need this line in your component.ts file (It's only for Angular <6):

import { } from '@types/googlemaps';

Here's an (basic/minimal) example for Angular 6:

/// <reference types="@types/googlemaps" />
map: google.maps.Map;
this.map = new google.maps.Map(....);

Basically, if you want to use it in Angular <6, you have to add it via the import method. In Angular 6+ you have to add it via the reference method. You shouldn't add both at the same time.

Hope I could help.