It is possible to interactively prompt users who downloaded your app, to rate the app and write a review on the App Store.
This option will work for apps which are live on the App Store.
Before requesting a new build (update), make the following changes in the settings of your app.
From the dashboard of your app access Application Settings:
Click on Platform Specific Options – > Rate App Settings:
Enter your app's Apple ID
Note: to find out your app's Apple ID log in to your account on itunesconnect.apple.com / navigate to "My apps" / "More" / "About This App".
Pick the activity which will trigger the "Rate App" popup message:
prompt at launch application, or
at relaunch from background
You can also personalize the message encouraging user to rate/review your app. If not the following message will appear:
"If you enjoy using 'bundleAppName' , would you mind taking a moment to rate it? It won't take more than a minute. Thanks for your support!"
The popup message will look like below:
Tapping on "Rate It Now" user will be taken to "Rating section of your app" from App Store. After signing in with his/her Apple credentials user will be able to rate your app/ submit a review of your app for the App Store.