Currency Converter Create a credentials.properties file at the root folder of the project, and set the key/value pair as follows: API_KEY="XXXX_XXXX_XXXX_XXXX" Demo apk available here: https://drive.google.com/file/d/1vWR1Q3XSqW9KN3O5RAxOEoVRFQb5xikD/view?usp=sharing