API key is hardcoded and retrievable from the application package. Since Android applications can be reverse engineered, embedding sensitive API credentials directly in the client application may allow unauthorized users to extract and misuse the key.

Transmission of a sensitive key in the URL over an unencrypted HTTP connection.  The request is sent over HTTP rather than HTTPS, meaning the key is transmitted in plaintext across the network. An attacker with the ability to monitor network traffic could intercept the request and obtain the key