iOS mobile gaming developer wanted

I want to make a mobile game for iOS that is similar to flappy bird. I would like to have bright/vibrant colors, be an endless runner, a community scoreboard ( which the user has the choice to post their scores), and for this game to become increasingly more difficult as the player progresses through the game. I don’t want anything that is impossible to beat, but very close to it. I would also need for you to integrate interstitial ads. My goal is to make money from ad revenue. Please make this game as addicting as possible. I can pay $850 for this project but that will have to be made I. Installments of $250 every two weeks. The pricing is negotiable. Please provide examples of past game similar to this, so that I can better make my rescission on who to choose for this project. If you have any questions, comments, or concerns, please message me and I will reply to you as soon as I can.