After having researched the issue to great length, we have not found a valid solution for our situation.
We have API keys for external SDKs and APIs which we are using in our app.
This link says to bind your key to a signing certificate. This is great if you have your own SDK or API, but for external elements where you have to provide your assigned key as a parameter, this is not an option.
The following link does not apply to our situation. Implementing (secure) Api Keys in an app
In addition, we have spent three days of trying different configurations as well as the ProGuard UI attempting to obfuscate our code using ProGuard without success.
We have also implemented AndroidManifest.xml key references, but they are clearly visible in a generated config.java class. Thus, this is also not a viable solution.
Securing source code is a minor priority. Our main concern is the security of the API keys.
Can anyone provide a possible solution? Is the DexGuard product a real solution when we cannot get ProGuard to work with a simple project?