Dear Sir,
We did many similar projects to your App, some of them were very complex.
We are international Game development company with HQ in London and we did over 160 mobile apps, games and software.
We have experts in all fields of App development, multiplayer, user interface, 2D, 3D interactions, modelars, graphic designers, server and backend and mobile options, iap.
Let me know more details and we can provide you detailed plan of work for your App with phases.
Thanks,
Miodrag