Google Play In-App Review API: rules and limits

In this guide

Why the dialog may not appear
Rules for how you use it
Designing around the quota
Testing

The API lets users rate your app without leaving it. Google describes it as a way to "prompt users to submit Play Store ratings and reviews without the inconvenience of leaving your app or game." The user picks 1 to 5 stars and can add a comment; once submitted, the review goes to the Play Store.

Why the dialog may not appear

A quota exists. Google says it "enforces a time-bound quota on how often a user can be shown the review dialog". Calling launchReviewFlow more than once in a short period (for example less than a month) "might not always display a dialog". The value "can be changed by Google Play without any notice."
You get no result. The Kotlin/Java guide says the API "does not indicate whether the user reviewed or not, or even whether the review dialog was shown." Continue your normal flow either way, and show no error to the user if the flow fails.
Requirements. Android 5.0 (API 21) or higher with the Play Store installed, and Play Core 1.8.0 or higher, per the overview page at retrieval time.

Rules for how you use it

Trigger after the user has experienced enough of the app to give useful feedback, and do not prompt excessively.
Do not ask questions before or while showing the card, including "Do you like the app?"
Show the card as is: no changes to size, opacity or shape, no overlay, and do not remove it programmatically.
Do not offer a button that triggers the API. Redirect to the Play Store for that case.
Request the ReviewInfo object ahead of time only when you are sure you will launch the flow; it expires.

On rewards: the pages I read do not address incentives. Rewarded ratings are not an option; see buy app reviews for the Play policy.

Designing around the quota

Pick one or two high-value moments (after a completed task) and stop there.
Never build logic that depends on the dialog having shown.
For a settings entry, link to your Play listing.
Collect private feedback separately: ask for feedback, not reviews.

Testing

Google says you can test without publishing to production using an internal test track or internal app sharing. Quota limits are not enforced for apps downloaded from the internal test track. With internal app sharing, reviews cannot be submitted. The conditions (account in the track, Play Store primary account, no existing review) are on Google's test page. See also why tester reviews stay private.

Google can change all of this. Re-check the pages above before each release. Not legal advice.

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