Rate In App

I’m looking for a professional to help me set up an app rate SYSTEM. The app needs to allow people to rate everything The rate I would like is standard rate and the payment method should be by PayPal with a one-time payment. My in-app rate system needs to be secure and reliable so that my users can have a smooth, worry-free experience when they purchase something on my app. The successful applicant must have experience in setting up a secure and crucial rate systems that ensure the safety of my customers. I would also like an overview of the different steps taken during the set up process.

Please let me know if you are available to help me in this endeavor.