Suggestions for basing a new app on an existing codebase?

I’m trying to quickly create a new (Ionic v1) app based on an existing (Ionic v1) codebase. The existing app is already in the Google and Apple stores. I’m changing the package name in the config.xml (com.xxx.yyy), creating a new app using Ionic services (so a new appId).

My question is, are there any gotchas I need to know about doing this? Anything that I need to be sure to do? Or would it be better to create a new app from scratch and copy all the code over to the new one?