Android : Re-branding an iOS Application (as compared to Android)

We purchased the source code to a certain Android and iOS application and now need to re-brand it before releasing it on the app stores. I'm quite familiar with Android, so that side wasn't an issue. However, I've never touched iOS apps before, so I have a few questions.

On the Android side, we changed the application name by changing several string resources. Then we changed the package name in the manifest.xml file (to make this a unique application in the eyes of Google Play) along with changing the package names in the affected class files. And compile.

Would iOS applications require something similar? Is there an equivalent to the Android string resources where I can change strings in one place and they are reused throughout the application? Also do iOS applications have some sort of unique ID, the equivalent of the Android's package name in the manifest.xml file? If I change this unique ID, does it impact the code in any way (in Android the package name corresponds to the main application Java package that starts the application).