You are able to change your account details or add your email address and/or phone number at any time from within the app, so long as you are logged in.
First, navigate to the menu, by tapping the menu icon at the top left of the app.
2. Tap 'Account' to navigate to your account details.
3. Here you can tap on the details you would like to change, type in the new information and select 'Save'.
NOTE: If you have signed up to the app with your phone number OR email address and want to include both in your account, you can follow the steps above to include both your email and phone number on the same app account.