NBA All-World currently requires a Google account to play. If you are using any provider other than Google (Gmail), don't worry- you can still use your existing email to create a Google account.
Here's how to create a Google account without changing your email:
- Go to the Google Account page
- Create account
- Enter your name
- Select Use my current email address instead
- Enter your existing non-Google email address
- Verify your email address by following the instructions provided