real time online quiz Trivia app for multiplayers with friendly cool UI design

i have a card game about trivia questions and i need to build a new project app for ios and android with Cool UI designs about this trivia questions challenges with different category and leader board score and users can create rooms for small network and challenges , also users can play online with different opponents globally. also you can subscribe with extra fees to allow more categories and more questions , its like similar as "Quiz up app" . also we link the card game with app such as calculating the score of card game with this app