How to report infringements on Google Play
You should complete an online form and send it to the Google Play legal team. They will then contact the app developer in question before establishing whether an infringement has taken place. If an infringement has occured, the Google Play team will remove the app.
Trademark Issues: https://support.google.com/legal/contact/lr_trademark?product=googleplay
Copyright Issues: https://support.google.com/legal/contact/lr_dmca?product=googleplay