Tap on your user profile at the bottom right in the main menu.
To create an account at all, you need to enter an email address - only then is it also possible to delete the account.
Scroll all the way down in your profile and click on 'Delete Account'.
Deletion cannot be undone - an empty account will be created and stored on your device if you wish to start anew with an empty account. However, there will be NO starting bonus for this account. If you no longer wish to use the app, simply remove it from your device. No personal data is stored in the empty account, and it will be automatically deleted after 4 weeks of inactivity.