Optimizing for iOS


I have been working on a single level game for the past year and am nearing completion. I originally built with the intention of releasing as a PC game but am realizing now I would like to also release for iOS. I packaged the project for iOS and added to my iPhone with Xcode, however it just shows an image of what looks like a floor, I hear sounds but cannot see anything else. I tested out the third person mobile template version, deployed to iPhone and that works fine. I am assuming my game isn’t optimized at all for mobile i.e. the textures are too large, lighting too involved, etc.

Is there an easy way to take a game you built and optimize it for mobile? Like is there a plugin out there, or do you have to do this manually? I fear I will have to rebuild the game from scratch but am hoping there is an easy way to just take what I have and convert so it works on mobile.

Thank you in advance for any suggestions!