two phones, change user on one phone

Unknown

I started playing on an iPhone and then moved to playing on a Galaxy. I would like to allow my son to start playing from the beginning on the iPhone.

I deleted the app from the iPhone and re-downloaded, but it automatically reloaded my data.

I do not want to erase my game. I just want to reset the iPhone so that a new user can start from scratch.

Is this possible? Thanks in advance.