You can edit your account information (including email preferences, devices, etc.) at your myOsmo page (https://my.playosmo.com).
After you log in, select 'Account' from the dropdown menu under your username (top right corner), then select any option from the menu on the left-hand side.
Also, please see our instructions for myOsmo account creation and management here:
https://assets.playosmo.com/static/downloads/GettingStartedWithmyOsmoAccountsProfiles.pdf