Game lags a lot(android),Game lags a lot

I am making a car game and have made a city with sketch up. That city is not huge, but still my editor and the game itself run slow after I have placed it in the world. I also marked the model as static, but no improvement…The graphics are not really HiFi, but still the game lags. I don’t get why, when games like vice city on android with huge cities run smoothly! can someone please help me??? I am using unity pro.,

If your city is one single object/mesh, there’s not much Unity can do to make it faster. You should split it up into multiple objects that can be culled/processed individually. You should also use Occlusion (Umbra) since you have pro. That really shines in city-like environments.

Also, games like Vice City are not a good comparison. They are built by large teams of processionals using very complex, custom built software. Making an open world game, even in Unity, is much more complicated than dropping in a mesh.

PS - it helps when you post screen shots for questions like this.