It’s impossible to change your email address but you can create a new account and duplicate your boards into your new account. Follow the next steps:
- Enter the app, SHARE the board(s) from your old account with the email address of the NEW account.
- Tap on logout twice and then sign-up with the new email address.
- Enter the board(s) and copy & paste all the content from the shared board(s) into the new board(s) that you will create in the NEW account.