How To Install

Install by add directly in manifest.json in folder Packages/manifest.json

for version 1.8.1

"com.google.play.review": "https://github.com/google-unity/in-app-review.git#1.8.1",

• dependency google.play.core 1.8.1, google.play.common 1.8.1, google.android.appbundle 1.8.0, external-dependency-manager 1.2.172

"com.google.play.core": "https://github.com/google-unity/google-play-core.git#1.8.1",
"com.google.play.common": "https://github.com/google-unity/google-play-common.git#1.8.1",
"com.google.android.appbundle": "https://github.com/google-unity/android-app-bundle.git#1.8.0",
"com.google.external-dependency-manager": "https://github.com/google-unity/external-dependency-manager.git#1.2.172",

Usages

using System.Collections;
using UnityEngine;
#if UNITY_IOS
using UnityEngine.iOS;
#elif UNITY_ANDROID
using Google.Play.Review;
#endif

public class AppRating : MonoBehaviour
{
#if UNITY_ANDROID
    private ReviewManager _reviewManager;
    private PlayReviewInfo _playReviewInfo;
    private Coroutine _coroutine;
#endif

    private void Start()
    {
#if UNITY_ANDROID
        _coroutine = StartCoroutine(InitReview());
#endif
    }

    public void RateAndReview()
    {
#if UNITY_IOS
        Device.RequestStoreReview();
#elif UNITY_ANDROID
        StartCoroutine(LaunchReview());
#endif
    }

#if UNITY_ANDROID
    private IEnumerator InitReview(bool force = false)
    {
        if (_reviewManager == null) _reviewManager = new ReviewManager();

        var requestFlowOperation = _reviewManager.RequestReviewFlow();
        yield return requestFlowOperation;
        if (requestFlowOperation.Error != ReviewErrorCode.NoError)
        {
            if (force) DirectlyOpen();
            yield break;
        }

        _playReviewInfo = requestFlowOperation.GetResult();
    }

    public IEnumerator LaunchReview()
    {
        if (_playReviewInfo == null)
        {
            if (_coroutine != null) StopCoroutine(_coroutine);
            yield return StartCoroutine(InitReview(true));
        }

        var launchFlowOperation = _reviewManager.LaunchReviewFlow(_playReviewInfo);
        yield return launchFlowOperation;
        _playReviewInfo = null;
        if (launchFlowOperation.Error != ReviewErrorCode.NoError)
        {
            DirectlyOpen();
            yield break;
        }
    }
#endif

    private void DirectlyOpen() { Application.OpenURL($"https://play.google.com/store/apps/details?id={Application.identifier}"); }
}

Knows Issue with unity 2021+

If you call RequestReviewFlow with Coroutine to display the review form in test environment (specifically Internal testing) but nothing happens and no error log appears in console.

The cause may be that the native plugin of in-app-review is missing when building the application, namely com.google.android.play.review and com.google.android.gms.play-services-tasks. So you can try enabling proguard to keep them in the build

-keep class com.google.android.play.core.** { *; }
-keep com.google.android.gms.play-** { *; }