Similar question about Bundle Name and Bundle Display Name have been asked, such as:
What's the difference between "bundle display name" and "bund
CFBundleDisplayName is for changing the text below the app icon on your device (and simulator). Yes this is supposed to be localized but there's no tangible penalty in performance to editing it or making it say whatever you want.
To edit this, you can change the "Bundle display name under "info" in the project:

CFBundleName not a clue. I can't figure out what this changes or why.