Not something I had considered. So for example a UI component that might load 3 different versions based on a string identifier, should instead use an enum which maps to integers? I say an enum because this would preserve readability of the code.
If you are interfacing with other APIs that use Strings, it may make sense to just pass those through. For example loading files from disk or pulling up UI classes from the OS library using some String identifier or something. It's hard to say without more context.