AFAIK. You have no way to verify that a user has rated your application. To rate the application, the user uses his iTunes account, about which you do not have information about the application.
The most likely is that as soon as you click on a bet in the application, you will receive coins. In other words:
"if you give a 5-star rating to our application, you will get 1000 coins"
- just a lie to push ppl to speed 5 ... The correct label could be:
"if you press this button, you will get 1000 coins, but we will really like that you will give us 5 stars" ...
But most ppl will not evaluate the application with this ...
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