If you are logged in to the app:
To change your password, click on the menu icon on the right-hand corner of the screen, and find the Account section. At the bottom of the page, you will see a Change Password button.
To change your email, click on the current email you already have entered in and delete it. Now you can enter in a new email.
If you aren't logged in and need to reset your password:
Just go to the log in screen in the app and click "Forgot password" at the bottom.