Hi,
I have been developing games for more than two years. I use Unity 3D game engine to develop games. Unity 3D provides perfect physics for the game.
I can provide you a free backend service with a admin panel. You can use it to manage your game, promotion, offers, etc as you see in the reference you have mentioned in description.
Please contact me for further discussion and don't forget to have a look on reviews I have got from my clients :)
Thank you!!