How to integrate Flutter Google Map for IOS and Android

Plugin google_maps_flutter: ^2.6.0

permission for Location

<key>NSLocationWhenInUseUsageDescription</key>
   <string>Your message requesting location permission.</string>
   <key>NSLocationAlwaysUsageDescription</key>
   <string>Your message requesting location permission.</string>

Or in your swift code, specify your API key in the application delegate ios/Runner/AppDelegate.swift:

import UIKit
import Flutter
import GoogleMaps

@UIApplicationMain
@objc class AppDelegate: FlutterAppDelegate {
  override func application(
    _ application: UIApplication,
    didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]?
  ) -> Bool {
   GMSServices.provideAPIKey("API-KEY")
    GeneratedPluginRegistrant.register(with: self)

    return super.application(application, didFinishLaunchingWithOptions: launchOptions)
  }
}

Location permission
Manifest File

<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />

Specify your API key in the application manifest android/app/src/main/AndroidManifest.xml:

<manifest ...
  <application ...
    <meta-data android:name="com.google.android.geo.API_KEY"
               android:value="YOUR KEY HERE"/>